Scielo RSS <![CDATA[Journal of Applied Oral Science]]> vol. 26 num. lang. en <![CDATA[SciELO Logo]]> <![CDATA[Bone repair access of BoneCeramic™ in 5-mm defects: study on rat calvaria]]> Abstract Objective: The aim of this study was to evaluate the osteoconductive potential of BoneCeramic™ on bone healing in rat calvaria 5-mm defects. Material and Methods: A 5-mm calvaria bone defect was induced in three groups and the defect was not filled with biomaterial [Clot Group (CG)], autogenous bone (AG), or Bone Ceramic Group (BCG). Animals were euthanized after 14 or 28 days and the bone tissue within the central area of the bone defect was evaluated. Results were compared using ANOVA and Tukey test (p&lt;0.05). Immunohistochemistry was performed using primary antibodies against osteocalcin, RUNX-2, TRAP, VEGF proteins, and 3-dimensional images of the defects in μCT were obtained to calculate bone mineral density (BMD). Results: In BCG, the defect was completely filled with biomaterial and new bone formation, which was statistically superior to that in the GC group, at both time-points (p&lt;0.001 for 14 days; p=0.002 for 28 days). TRAP protein showed weak, RUNX-2 showed a greater immunolabeling when compared with other groups, VEGF showed moderate immunostaining, while osteocalcin was present at all time-points analyzed. The μCT images showed filling defect by BCG (BMD= 1337 HU at 28 days). Conclusion: Therefore, the biomaterial tested was found to be favorable to fill bone defects for the reporting period analyzed. <![CDATA[Evaluation of the sealing ability of different root canal sealers: a combined SEM and micro-CT study]]> Abstract Objective: The purpose of this study was to analyze the ability of multiple compounds to seal the dental tubules using scanning electron microscopy (SEM) and micro-computed tomogra-phy (micro-CT). Material and Methods: Twenty-four single-root human mandibular premolars were selected and instrumented with nickel-titanium rotary file and the final file size was #40/06. They were then randomly allocated into 2 groups, and all samples were filled with single cone gutta-percha (#40/06) and one of the tested sealers (AH Plus and EndoSequence BC sealers). All specimens were scanned using micro-CT and then three from each group were randomly selected for SEM analysis. Results: According to SEM, both root canal sealers showed sufficient adaptation to dentin along the whole length of the root canal, though the coronal sections presented superior sealing than the apical sections. Micro porosity analyses revealed that the volume of closed pores and the surface of closed pores had the largest values in the coronal sections, followed by the middle and the apical sections for both sealants (p&lt;0.05). However, no significant difference was observed for those two parameters between AH Plus and EndoSequence BC sealers in any of the three sections (p&gt;0.05), whereas they were larger in the apical section when the AH Plus sealer was used. Conclusions: By using the single cone technique, neither EndoSequence or AH Plus pro-vides a porosity-free root canal filling. The EndoSequence BC sealer may have similar sealing abilities regarding the whole root canal as the AH Plus sealer. A better sealing effect could be obtained in the coronal and middle sections of a root canal than the apical part by using the tested sealers. <![CDATA[Alveolar bone repair with strontium- containing nanostructured carbonated hydroxyapatite]]> ABSTRACT Objective: This study aimed to evaluate bone repair in rat dental sockets after implanting nanostructured carbonated hydroxyapatite/sodium alginate (CHA) and nanostructured carbonated hydroxyapatite/sodium alginate containing 5% strontium microspheres (SrCHA) as bone substitute materials. Methods: Twenty male Wistar rats were randomly divided into two experimental groups: CHA and SrCHA (n=5/period/group). After one and 6 weeks of extraction of the right maxillary central incisor and biomaterial implantation, 5 μm bone blocks were obtained for histomorphometric evaluation. The parameters evaluated were remaining biomaterial, loose connective tissue and newly formed bone in a standard area. Statistical analysis was performed by Mann-Withney and and Wilcoxon tests at 95% level of significance. Results: The histomorphometric results showed that the microspheres showed similar fragmentation and bio-absorbation (p&gt;0.05). We observed the formation of new bones in both groups during the same experimental periods; however, the new bone formation differed significantly between the weeks 1 and 6 (p=0.0039) in both groups. Conclusion: The CHA and SrCHA biomaterials were biocompatible, osteoconductive and bioabsorbable, indicating their great potential for clinical use as bone substitutes. <![CDATA[Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up]]> ABSTRACT Objective: The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Material and Methods: Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. Results: All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups. Conclusions: The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group. <![CDATA[Effect of erosive challenges on deciduous teeth undergoing restorative procedures with different adhesive protocols - an <em>in vitro</em> study]]> ABSTRACT Objective: To evaluate the effect of erosive challenges on the tooth- restoration interface of deciduous teeth treated with different adhesive protocols. Material and Methods: Deciduous molars were cut mesiodistally, then embedded, abraded and polished (n=80). Samples were randomly divided according to the adhesive system used into: G1 (Adper Single Bond2®, etch-and-rinse), G2 (Universal Single Bond®, self-etching), G3 (OptibondFL®, etch-and-rinse with Fluoride) and G4 (BondForce®, self-etching with Fluoride). After standardized cavity preparation (2 mm diameter x 2 mm depth), adhesive systems were applied and samples were restored (composite resin Z350®). Half of the samples were exposed to erosive/abrasive cycles (n = 10, each adhesive group), and the other half (control group; n = 10) remained immersed in artificial saliva. For microleakage analysis, samples were submersed in methylene blue and analyzed at 40x magnifications. Cross-sectional microhardness (CSMH) was carried out (50 g/5 s) at 25 μm, 50 μm, and 100 μm from the eroded surface and at 25 μm, 75 μm, and 125 μm from the enamel bond interface. Results: Regarding microleakage, 7.5% of the samples showed no dye infiltration, 30% showed dye infiltration only at the enamel interface, and 62.5% showed dye infiltration through the dentin-enamel junction, with no difference between groups (p≥0.05). No significant difference was observed in CSMH at different depths (two-way ANOVA, p≥0.05). Conclusions: We did not observe significant changes in microleakage or CSMH after erosive/abrasive challenges in deciduous teeth treated with different adhesive protocols (etch-and-rinse and self-etching adhesives, with and without fluoride). <![CDATA[To what extent does hyaluronic acid affect healing of xenografts? A histomorphometric study in a rabbit model]]> ABSTRACT Among the many graft materials that have been used for the treatment of bone defects in oral and maxillofacial regions is xenograft. To improve osteoconductive effects of xenografts, they have been combined with various biocompatible materials, such as hyaluronic acid and bone morphogenetic protein. Objective: To determine bone-healing capacity of high molecular weight hyaluronic acid (HA) combined with xenograft in rabbit calvarial bone defects. Material and methods: Ten adult male New Zealand rabbits (mean weight 3 kg) were included in the study. Three 6-mm-diameter bicortical cranial defects were created on calvarial bone of all rabbits. These defects were filled as follows: a) xenograft; b) HA+xenograft; c) autograft. One month after the first operation, rabbits were sacrificed. Specimens were evaluated histomorphometrically. Results: Considering multiple comparisons, differences regarding new bone were statistically significant between all groups (p&lt;0.05). The volume of residual graft was significantly decreased in HA group compared to xenograft group (p=0.035). Marrow space, trabecular thickness (TbTh), trabecular width (TbWi), trabecular separation (TbSp), and number of node: number of terminus (NNd:NTm) in the autograft group were significantly better than xenograft and HA groups (p&lt;0.05). However, regarding marrow space, TbTh, TbWi, TbSp, and NNd:NTm values, xenograft and HA groups showed similar results and the difference were not significant (p&gt;0.05). Conclusion: These results support that high molecular weight hyaluronic acid could contribute to the healing of xenograft by improving the percentage of new bone formation and reducing the percentage of residual graft. However, HA did not significantly affect the quality of newly formed bone assessed by microarchitectural parameters. <![CDATA[Structural and mechanical properties of a giomer-based bulk fill restorative in different curing conditions]]> ABSTRACT Objective: The main goal of this study was to compare the polymerization degree of bulk-fill giomer resin cured with three different light-curing units (LCUs): a polywave third-generation (Valo); a monowave (DemiUltra: DU); and a second-generation LED (Optima 10: Opt) LCUs by using structural and mechanical properties. Material and methods: Giomer samples of 2 and 4 mm cured with three LCUs were employed in vitro analysis. The degree of curing (DC%) was determined with Fourier-Transform Infrared Spectroscopy (FTIR). Microstructural features were observed with scanning electron microscopy (SEM). Flexural strength (FS), compression strength (CS), elastic modulus and fracturing strain were determined for mechanical properties. Surface microhardness (SMH) values were also measured. Oneway ANOVA, two-way analysis of variance and Tukey multiple comparison tests were used for statistically analyzing the FS and SMH. Results: DC% values were 58.2, 47.6, and 39.7 for the 2 mm samples cured with DU, Opt., and Valo LCUs, respectively. DC% values of the 4 mm samples were 50.4, 44.6, and 38.2 for DU, Opt, and Valo, respectively. SMH values were Valo, Opt&lt;DU at top of the samples; Valo&lt;DU, Opt at 2 mm, and DU, Valo&lt;Opt at 4 mm depth. Giomer samples cured with Opt and DU exhibited higher FS values than Valo. CS values were similar but compressive modulus and fracturing strain (%) varied depending on the curing protocol. Conclusions: Based on the results, it can be concluded that curing device and protocol strongly affect crosslinking reactions and thus DC%, SMH, compressive modulus and strain at break values. Consequently, it can be deduced that curing protocol is possibly the most important parameter for microstructure formation of highly-filled composite restoratives because it may bring some structural defects and physical frailties on restorations due to lower degree of polymerization. <![CDATA[Influence of skin cold sensation threshold in the occurrence of dental sensitivity during dental bleaching: a placebo controlled clinical trial]]> Abstract Objective This study verified the occurrence of dental sensitivity in patients submitted to a 35% hydrogen peroxide based product (Whiteness HP Maxx 35% – FGM), skin cold sensation threshold (SCST) and its influence on dental sensitivity. Material and Methods Sixty volunteers were divided into 4 groups (n = 15), according to SCST (low: GI and GIII, and high: GII and IV) and bleaching treatment (hydrogen peroxide: GI and GII, and placebo: GIII and GIV). SCST was determined in the inner forearm for 6 different times using a neurosensory analyzer, the TSA II (Medoc Advanced Medical Systems, Ramat Yishai, Northern District, Israel). Dental sensitivity measurements were performed 10 different times using a thermal stimulus and an intraoral device attached to TSA II, positioned in the buccal surface of the upper right central incisor. Spontaneous dental sensitivity was also determined using the Visual Analogue Scale (VAS). Data were submitted to Student's t-test and Pearson's Correlation Test (α=0.05). SCST remained the same during bleaching treatment. Results Distinct responses of dental sensitivity were found in patients with low and high SCST during the first and third bleaching session (p≤0.05). The teeth submitted to the bleaching treatment became more sensitive to cold than those treated with placebo. Moreover, data obtained with TSA and VAS presented moderate correlation. Conclusions Bleaching treatment increased dental sensitivity and skin cold sensation threshold might represent a determining factor in this occurrence, since low and high SCST patients had different responses to the thermal stimulus in the teeth. <![CDATA[Determination of the effective anticandidal concentration of denture cleanser tablets on some denture base resins]]> Abstract Objective Although the effectiveness of chemical cleansing against Candida albicans biofilm has been shown, the effective concentration of denture cleanser tablets has not been studied. The aim of this study was to assess the effect of three denture materials against Candida albicans biofilm and to determine effective concentrations of denture cleanser tablets. Material and methods The surface-roughness of Acron-hi™, QC-20™ and Deflex™ (n=45 per resin) resins was standardized by using a profilometer and their contact angle or surface free energy was calculated. C. albicans biofilm was formed on all three resins and were treated with Polident 3 min™, Corega™ and Fittydent™ cleanser solutions at various concentrations and both resin-biofilm and cleanser-biofilm interest were determined by using a MTT protocol according to the European Committee on Antimicrobial Susceptibility Testing's antifungal susceptibility testing (AFST-EUCAST). Scanning electron microscopy was used to compare the efficacy of different resin materials against C. albicans biofilm. Anticandidal activity and surface free energy statistical parameters were calculated by using 3-way and 1-way ANOVA, respectively (p&lt;0.05). Results Polident 3 min™ and Corega™ tablets significantly inhibited (p&lt;0.05) the proliferation of C. albicans against all denture resins at 27-37 mg/mL. Scanning electron microscopy results indicated that there was no significant difference among resin specimens regarding biofilm formation on dentures. We failed to find a significant relationship between surface free energy and the anticandidal effect of resin types. However, the polarity value of the resins was statistically associated with their anticandidal activity. Conclusions The polarity of the resins, the concentrations of tablets and the chemical content of the cleanser may directly affect C. albicans biofilm formations. Polident 3 min™ and Corega™ tablets should be suggested for patients who use any denture resin types, whereas the Fittydent™ tablet should only be proposed for those who use Deflex™, when two tablets are dropped into 150 mL water. <![CDATA[Randomized clinical trial of encapsulated and hand-mixed glass-ionomer ART restorations: one-year follow-up]]> Abstract Objective This prospective, randomized, split-mouth clinical trial evaluated the clinical performance of conventional glass ionomer cement (GIC; Riva Self-Cure, SDI), supplied in capsules or in powder/liquid kits and placed in Class I cavities in permanent molars by the Atraumatic Restorative Treatment (ART) approach. Material and Methods A total of 80 restorations were randomly placed in 40 patients aged 11-15 years. Each patient received one restoration with each type of GIC. The restorations were evaluated after periods of 15 days (baseline), 6 months, and 1 year, according to ART criteria. Wilcoxon matched pairs, multivariate logistic regression, and Gehan-Wilcoxon tests were used for statistical analysis. Results Patients were evaluated after 15 days (n=40), 6 months (n=34), and 1 year (n=29). Encapsulated GICs showed significantly superior clinical performance compared with hand-mixed GICs at baseline (p=0.017), 6 months (p=0.001), and 1 year (p=0.026). For hand-mixed GIC, a statistically significant difference was only observed over the period of baseline to 1 year (p=0.001). Encapsulated GIC presented statistically significant differences for the following periods: 6 months to 1 year (p=0.028) and baseline to 1 year (p=0.002). Encapsulated GIC presented superior cumulative survival rate than hand-mixed GIC over one year. Importantly, both GICs exhibited decreased survival over time. Conclusions Encapsulated GIC promoted better ART performance, with an annual failure rate of 24%; in contrast, hand-mixed GIC demonstrated a failure rate of 42%. <![CDATA[Psychopathological profile and quality of life of patients with oral lichen planus]]> Abstract Objectives Oral lichen planus (OLP) is a chronic, multifocal, sometimes painful, inflammatory disease of the oral mucosa. OLP can predispose development of psycho-emotional disorders. Until now, the relationship between the severity of lichen planus and the psychological profile of patients (psychological well-being, perceived stress and pain coping strategies) has never been studied. Material and Methods Study was conducted on 42 OLP patients. Number of sites involved, severity and activity score of OLP were evaluated. Psychological tests were used to evaluate patients’ psycho-emotional condition. The mean duration time of symptomatic OLP was 43 months. Results We detected that the longer the duration of subjective symptoms, the poorer the quality of life and the higher the level of perceived stress (PSS). Also, the higher the PSS results, the greater the anxiety and depression on Hospital Anxiety and Depression Scale (HADS). Likewise, higher level of depression in HADS was strongly correlated with worse quality of life. (p≤0.05). Conclusions In this study, we detected a relationship between duration of the disease, level of perceived stress and quality of life. The longer the disease lasts, the higher it tends to catastrophize. This may influence development or increase of the anxiety and depression and may decrease patients’ quality of life. <![CDATA[Two mechanisms of oral malodor inhibition by zinc ions]]> Abstract Objectives The aim of this study was to reveal the mechanisms by which zinc ions inhibit oral malodor. Material and Methods The direct binding of zinc ions to gaseous hydrogen sulfide (H2S) was assessed in comparison with other metal ions. Nine metal chlorides and six metal acetates were examined. To understand the strength of H2S volatilization inhibition, the minimum concentration needed to inhibit H2S volatilization was determined using serial dilution methods. Subsequently, the inhibitory activities of zinc ions on the growth of six oral bacterial strains related to volatile sulfur compound (VSC) production and three strains not related to VSC production were evaluated. Results Aqueous solutions of ZnCl2, CdCl2, CuCl2, (CH3COO)2Zn, (CH3COO)2Cd, (CH3COO)2Cu, and CH3COOAg inhibited H2S volatilization almost entirely. The strengths of H2S volatilization inhibition were in the order Ag+ &gt; Cd2+ &gt; Cu2+ &gt; Zn2+. The effect of zinc ions on the growth of oral bacteria was strain-dependent. Fusobacterium nucleatum ATCC 25586 was the most sensitive, as it was suppressed by medium containing 0.001% zinc ions. Conclusions Zinc ions have an inhibitory effect on oral malodor involving the two mechanisms of direct binding with gaseous H2S and suppressing the growth of VSC-producing oral bacteria. <![CDATA[Debris extrusion and foraminal deformation produced by reciprocating instruments made of thermally treated NiTi wires]]> Abstract Objective To evaluate the amount of apically extruded debris, percentage of foraminal enlargement and apical foramen (AF) deformation that occurred during root canal preparation with different reciprocation systems: Reciproc, WaveOne (M-Wire), and ProDesign R (Shape Memory Technology Wire) at two different working lengths (WLs): 0.0 and 1.0 mm beyond the AF. Material and methods The AF of 120 root canals in 60 mesial roots of mandibular molars were photographed with stereomicroscope and randomly assigned into four groups: manual, Reciproc (REC), WaveOne (WO), and ProDesign R (PDR); subsequently, they were further subdivided according to the WL (n=15). Teeth were instrumented, coupled to a dual collecting chamber, and then another photograph of each AF was captured. Extrusion was analysed by determining the weight of extruded debris. Each AF diameter was measured in pre- and post-instrumentation images to determine deformation, which was analysed, and afterwards the final format of AFs was classified (circular/oval/deformed). Results We found no significant differences when analysing each system at different WLs. When considering each WL, REC and WO showed highest extrusion values (P&lt;.05); for AF enlargement, differences were observed only for WO, when it was used beyond the AF; differences were observed among M-Wire groups beyond the AF (P&lt;.05). AF deformation was observed in all groups; PDR showed the lowest AF deformation values at both WLs; M-Wire groups showed 50% strain beyond the AF. Conclusion Authors concluded that beyond the apical limit, the alloy and taper are important aspects when considering extrusion and deformation. <![CDATA[Effects of orofacial myofunctional therapy on masticatory function in individuals submitted to orthognathic surgery: a randomized trial]]> Abstract Objectives: The esthetic and functional results of orthognathic surgery of severe dentofacial deformities are predictable, however there are differences regarding the effects on stomatognathic system. The aim was to investigate the effects of orofacial myofunctional therapy (OMT) on the masticatory function in individuals with dentofacial deformity submitted to orthognathic surgery (OGS). Material and Methods: Forty-eight individuals (18-40 years) were evaluated, 14 undergoing OMT (treated group-TG), 10 without this treatment (untreated group-UTG) and 24 in a control group with normal occlusion; for clinical aspects the data of an individual was missed (n=46). Chewing was performed using the Expanded protocol of orofacial myofunctional evaluation with scores (OMES-E). Muscle tone and mobility were also analyzed before (P0), three (P1) and six months (P2) after OGS. Surface electromyography of the masseter and temporalis muscles was performed, considering the parameters amplitude and duration of act and cycle, and the number of masticatory cycles. The OMT consisted of ten therapeutic sessions along the postoperative period. The results were compared using parametric and non-parametric tests. Results: TG showed higher scores in P1 and P2 than P0; for the masticatory type the scores in P2 were significantly higher than P0. In addition, the proportion of individuals with adequate tone of lower lip and adequate tongue mobility for TG increased significantly from P1 and P2 in relation to P0. The EMG results showed a decrease in act and cycle duration in P2 in relation to P0 and P1 for the TG; furthermore the values were close to controls. An increase in the number of cycles from P0 to P2 was also observed, indicating faster chewing, which may be attributed to an improvement of balanced occlusion associated with OMT. Conclusion: There were positive effects of OMT on the clinical and electromyography aspects of chewing in individual submitted to orthognathic surgery. <![CDATA[Oral health-related quality of life of children with oral clefts and their families]]> Abstract Oral health problems can influence people's Quality of Life (QoL) because of pain, discomfort, limitations, and other esthetics problems, affecting their social life, feeding, daily activities, and the individual's well-being. Objective: To compare oral health-related quality of life (OHRQoL) of children with and without oral clefts and their families. Materials and Methods: 121 children aged from 2 to 6 years, from both sexes, enrolled in the treatment routine of the Pediatric Dentistry Clinics of a Dental School and a Hospital for Cleft Treatment were divided into two groups: Group 1 - children with cleft lip and palate; Group 2 - children without cleft lip and palate. The OHRQoL was assessed using the validated Portuguese version of the Early Childhood Oral Health Impact Scale (B-ECOHIS). The questionnaire was answered individually, only once, at a private place. Mann-Whitney U test was used to verify differences between groups. Spearman's Rho test was used to associate sex and age with quality of life. The level of significance was set at 5% (p&lt;0.05). Results: According to the parents’ perception on the OHRQoL of children with and without cleft lip and palate, oral health of children with oral clefts (Group 1) had a statistically significant impact on OHRQoL. The correlation of sex with impact on OHRQoL did not show statistically significant differences. On the other hand, the higher the age the higher the impact on QoL. Conclusions: The group comparison revealed that the cleft lip and palate negatively impacted on OHRQoL of 2 to 6-year-old children and their parents. <![CDATA[Effect of filler size and filler loading on wear of experimental flowable resin composites]]> Abstract The relationship between wear resistance and filler size or filler loading was clarified for the universal resin composite; however, their relationship in flowable resin composites has not been clarified. Objectives: The purpose of this study was to investigate the effect of filler size and filler loading on wear of experimental flowable resin composites by using a cyclic loading device. Material and Methods: Nine experimental flowable resin composites consisting of three different sizes (70, 200 and 400 nm) and loading (50, 55 and 60 wt%) of filler were prepared. Bowl-shaped cavities were prepared on a flat surface of ceramic blocks using a No. 149 regular cut diamond point. The cavities were treated with a silane coupling agent and an all-in-one adhesive and then filled with each experimental flowable resin composite. The restored surfaces were finished and polished with a 1500-grit silicon carbide paper. The specimens were subjected to an in vitro two-body wear test using a cyclic loading device. The localized worn surfaces were evaluated at 10,000, 20,000, 30,000, and 40,000 cycles using a computer-controlled three-dimensional measuring microscope (n=5). The volumetric wear loss of the materials was calculated automatically by the equipment. Data were statistically analyzed with two-way ANOVA and post hoc Tukey test. Results: Two-way ANOVA showed that the filler size significantly influenced wear volume (p&lt;0.003), but the filler loading did not have a significant effect (p&gt;0.05). A post hoc Tukey test detected significant differences in filler size between 70 nm and 400 nm, and 200 nm and 400 nm (p&lt;0.007). Conclusion: The experimental flowable resin composite containing a mean filler size of 400 nm exhibited significantly lower wear resistance in two-body wear compared with those containing mean filler sizes of 200 nm or 70 nm. <![CDATA[Effects of mineral trioxide aggregate, Biodentine<sup>TM</sup> and calcium hydroxide on viability, proliferation, migration and differentiation of stem cells from human exfoliated deciduous teeth]]> Abstract Objective: The aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA), calcium hydroxide (CH) and BiodentineTM (BD) on stem cells from human exfoliated deciduous teeth (SHED) in vitro. Material and Methods: SHED were cultured for 1 – 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL), and tested for viability (MTT assay) and proliferation (SRB assay). Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1) was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning) and culture medium supplemented with 20% FBS were used as controls. Results: MTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA) (p&lt;0.05). In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH) (p&lt;0.05). A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21. Conclusion: Our results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population. <![CDATA[Reliability of light microscopy and a computer-assisted replica measurement technique for evaluating the fit of dental copings]]> Abstract The aim of this in vitro study was to assess the reliability of two measurement systems for evaluating the marginal and internal fit of dental copings. Material and Methods: Sixteen CAD/CAM titanium copings were produced for a prepared maxillary canine. To modify the CAD surface model using different parameters (data density; enlargement in different directions), varying fit was created. Five light-body silicone replicas representing the gap between the canine and the coping were made for each coping and for each measurement method: (1) light microscopy measurements (LMMs); and (2) computer-assisted measurements (CASMs) using an optical digitizing system. Two investigators independently measured the marginal and internal fit using both methods. The inter-rater reliability [intraclass correlation coefficient (ICC)] and agreement [Bland-Altman (bias) analyses]: mean of the differences (bias) between two measurements [the closer to zero the mean (bias) is, the higher the agreement between the two measurements] were calculated for several measurement points (marginal-distal, marginal-buccal, axial-buccal, incisal). For the LMM technique, one investigator repeated the measurements to determine repeatability (intra-rater reliability and agreement). Results: For inter-rater reliability, the ICC was 0.848-0.998 for LMMs and 0.945-0.999 for CASMs, depending on the measurement point. Bland-Altman bias was −15.7 to 3.5 μm for LMMs and −3.0 to 1.9 μm for CASMs. For LMMs, the marginal-distal and marginal-buccal measurement points showed the lowest ICC (0.848/0.978) and the highest bias (-15.7 μm/-7.6 μm). With the intra-rater reliability and agreement (repeatability) for LMMs, the ICC was 0.970-0.998 and bias was −1.3 to 2.3 μm. Conclusion: LMMs showed lower interrater reliability and agreement at the marginal measurement points than CASMs, which indicates a more subjective influence with LMMs at these measurement points. The values, however, were still clinically acceptable. LMMs showed very high intra-rater reliability and agreement for all measurement points, indicating high repeatability. <![CDATA[Preemptive use of etodolac on tooth sensitivity after in-office bleaching: a randomized clinical trial]]> Abstract Purpose: This study determined the effectiveness of the preemptive administration of etodolac on risk and intensity of tooth sensitivity and the bleaching effect caused by in-office bleaching using 35% hydrogen peroxide. Material and methods: Fifty patients were selected for this tripleblind, randomized, crossover, and placebo-controlled clinical trial. Etodolac (400 mg) or placebo was administrated in a single-dose 1 hour prior to the bleaching procedure. The whitening treatment with 35% hydrogen peroxide was carried out in two sessions with a 7-day interval. Tooth sensitivity was assessed before, during, and 24 hours after the procedure using the analog visual scale and the verbal rating scale. Color alteration was assessed by a bleach guide scale, 7 days after each session. Relative risk of sensitivity was calculated and adjusted by session, while overall risk was compared by the McNemar's test. Data on the sensitivity level of both scales and color shade were subjected to Friedman, Wilcoxon, and Mann-Whitney tests, respectively (α=0.05). Results: The preemptive administration of etodolac did not affect the risk of tooth sensitivity and the level of sensitivity reported, regardless of the time of evaluation and scale used. The sequence of treatment allocation did not affect bleaching effectiveness, while the second session resulted in additional color modification. The preemptive administration of etodolac in a single dose 1 hour prior to in-office tooth bleaching did not alter tooth color, and the risk and intensity of tooth sensitivity reported by patients. Conclusion: A single-dose preemptive administration of 400 mg of etodolac did not affect either risk of tooth sensitivity or level of sensitivity reported by patients, during or after the in-office tooth bleaching procedure. <![CDATA[Can whitening toothpastes maintain the optical stability of enamel over time?]]> Abstract Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth. Objective: To evaluate the effect of cigarette smoking-toothbrushing-cycling (CSTC) with whitening toothpastes on the roughness and optical behavior of bovine enamel for eight weeks. Material and Methods: Thirty bovine dentin/enamel discs, 8.0 mm in diameter and 2.0 mm thick, were randomly divided into three groups according to the toothpastes: whitening (Colgate Luminous White - CW and Oral B 3D White - OW), and a non-whitening (Colgate - C). The roughness, color (CIE L*a*b* system), translucency and gloss were measured before and after the specimens were submitted to CSTC. The topography of the specimens was analyzed by scanning electron microscopy. During the first week, the specimens were daily subjected to the consumption of 20 cigarettes and brushed (40 strokes/100 g) with the toothpastes' slurries. Thereafter, the CSTC was weekly applied in an accumulated model (140 cigarettes/280 strokes) for seven weeks. The data were submitted to two-way ANOVA, Tukey's HSD test, and paired-t test (α=0.05). Results: The three toothpastes produced significant changes in roughness, color, translucency and gloss (p&lt;0.05). After eight weeks, the roughness and the gloss produced by the three toothpastes were similar (p&gt;0.05), while OW produced the lowest color change and the translucency of C was lower than that of CW (p&lt;0.05). The three toothpastes produced a significant decrease in L* values and a significant increase in a* values after eight weeks (p&lt;0.05). No significant difference in the b* coordinate was found for OW (p=0.13) There were topographic changes in the enamel surfaces. Conclusions: The whitening toothpastes increased the roughness, changed the topography and were not able to maintain the optical stability of enamel exposed over eight weeks. <![CDATA[3-D finite element analysis of the effects of post location and loading location on stress distribution in root canals of the mandibular 1<sup>st</sup> molar]]> Abstract Objective The purpose of this study was to evaluate, by using finite element analysis, the influence of post location and occlusal loading location on the stress distribution pattern inside the root canals of the mandibular 1st molar. Material and Methods Three different 3-D models of the mandibular 1st molar were established: no post (NP) – a model of endodontic and prosthodontic treatments; mesiobuccal post (MP) – a model of endodontic and prosthodontic treatments with a post in the mesiobuccal canal; and distal post (DP) – a model of endodontic and prosthodontic treatments with a post in the distal canal. A vertical force of 300 N, perpendicular to the occlusal plane, was applied to one of five 1 mm2 areas on the occlusal surface; mesial marginal ridge, distal marginal ridge, mesiobuccal cusp, distobuccal cusp, and central fossa. Finite element analysis was used to calculate the equivalent von Mises stresses on each root canal. Results The DP model showed similar maximum stress values to the NP model, while the MP model showed markedly greater maximum stress values. The post procedure increased stress concentration inside the canals, although this was significantly affected by the site of the force. Conclusions In the mandibular 1st molar, the distal canal is the better place to insert the post than the mesiobuccal canal. However, if insertion into the mesiobuccal canal is unavoidable, there should be consideration on the occlusal contact, making central fossa and distal marginal ridge the main functioning areas. <![CDATA[The effects of different restorative materials on periodontopathogens in combined restorative-periodontal treatment]]> Abstract Objective The aim of the study was to evaluate the association between subgingival restorations and the target periodontopathogenic bacteria (Pg, Td and Pi) in subgingival biofilm during one year after combined restorative-periodontal treatment. Material and Methods Seventeen systemically healthy subjects, who were positive for the presence of three cervical lesions associated with gingival recessions in three different adjacent teeth, were included in the study. A total of 51 combined defects were treated with connective tissue graft plus a nanofilled composite resin (NCR+CTG), a resin-modified glass ionemer cement (RMGI+CTG) and a fluoride-releasing resin material with pre-reacted glass (PRG), called giomer (Giomer+CTG). Periodontal clinical measurements and subgingival plaque samples were obtained from all combined defects at baseline and at 6 and 12 months after the surgery. The number of bacteria were evaluated by the real-time polymerase chain reaction (qPCR) method. Results No statistically significant difference in the amount of DNA copies of Pg, Td and Pi was observed in any of the groups at any time points (p&gt;0.05). In addition, there was no statistically significant difference in the amount of DNA copies of the bacteria at baseline and at 6 and 12 months postoperatively, regardless of treatment group (p&gt;0.05). Conclusion This study suggests that subgingivally placed NCR, RMGI and giomer restorations can show similar effects on periodontopathogenic bacteria in the treatment of gingival recessions that are associated with noncarious cervical lesions (NCCLs). <![CDATA[Comparison of deflection forces of esthetic archwires combined with ceramic brackets]]> Abstract Coated archwires and ceramic brackets have been developed to improve facial esthetics during orthodontic treatment. However, their mechanical behavior has been shown to be different from metallic archwires and brackets. Therefore, the aim of this study was to compare the deflection forces in coated nickel-titanium (NiTi) and esthetic archwires combined with ceramic brackets. Material and Methods Non-coated NiTi (NC), rhodium coated NiTi (RC), teflon coated NiTi (TC), epoxy coated NiTi (EC), fiber-reinforced polymer (FRP), and the three different conventional brackets metal-insert polycrystalline ceramic (MI-PC), polycrystalline ceramic (PC) and monocrystalline ceramic (MC) were used. The specimens were set up on a clinical simulation device and evaluated in a Universal Testing Machine (Instron). An acrylic device, representative of the right maxillary central incisor was buccolingually activated and the unloading forces generated were recorded at 3, 2, 1 and 0.5 mm. The speed of the testing machine was 2 mm/min. ANOVA and Tukey tests were used to compare the different archwires and brackets. Results The brackets presented the following decreasing force ranking: monocrystalline, polycrystalline and polycrystalline metal-insert. The decreasing force ranking of the archwires was: rhodium coated NiTi (RC), non-coated NiTi (NC), teflon coated NiTi (TC), epoxy coated NiTi (EC) and fiber-reinforced polymer (FRP). At 3 mm of unloading the FRP archwire had a plastic deformation and produced an extremely low force in 2; 1 and 0.5 mm of unloading. Conclusion Combinations of the evaluated archwires and brackets will produce a force ranking proportional to the combination of their individual force rankings. <![CDATA[Demetallization of <em>Enterococcus faecalis</em> biofilm: a preliminary study]]> Abstract Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels. <![CDATA[Comparison of primary human gingival fibroblasts from an older and a young donor on the evaluation of cytotoxicity of denture adhesives]]> Abstract Denture adhesives (DA) improve the retention and stability of ill-fitting dentures, especially for older adults. These materials should be biocompatible, i.e., they cannot cause undesired biological responses and be non-cytotoxic to oral tissues. However, in vitro testing of DA biocompatibility employing primary cell culture may possibly be affected by other factors, such as the donor age. Objective To compare the cytotoxicity of three different denture adhesives when assessed in primary gingival fibroblasts from a young donor or from an older donor, as well as the release of the basic fibroblast growth factor (bFGF), and the inflammatory response marker interleukin-6 (IL-6). Material and Methods Gingival fibroblasts isolated from a 30- and a 62-year-old donor were assayed for proliferation (1-7 days) and sensitivity to latex (positive control). Fibroblasts were indirectly exposed to Corega Ultra (cream), Corega powder and Fixodent Original for a 24 h period and assayed by XTT and Crystal Violet tests. The release of IL-6 and bFGF by exposed cells was determined by ELISA. Results While cells from the young donor presented higher cell growth after 7 days, the sensitivity to increasing concentrations of latex extracts was very similar between young and older cells. Both XTT and CVDE detected no difference between the DA and the control group. All materials induced higher levels of IL-6 and bFGF compared to control. Cells from the older donor exposed to Corega Ultra released lower levels of cytokine and growth factor. Conclusions All materials were considered non-cytotoxic, but affected cytokine and growth factor release. The biological differences found between fibroblasts from both donors could be due to individual or age-related factors. The authors suggest the use of cells from older donors on studies of dental products aimed at older patients, to better simulate their physiological response. <![CDATA[Effect of γ-lactones and γ-lactams compounds on <em>Streptococcus mutans</em> biofilms]]> Abstract Considering oral diseases, antibiofilm compounds can decrease the accumulation of pathogenic species such as Streptococcus mutans at micro-areas of teeth, dental restorations or implant-supported prostheses. Objective To assess the effect of thirteen different novel lactam-based compounds on the inhibition of S. mutans biofilm formation. Material and methods We synthesized compounds based on γ-lactones analogues from rubrolides by a mucochloric acid process and converted them into their corresponding γ-hydroxy-γ-lactams by a reaction with isobutylamine and propylamine. Compounds concentrations ranging from 0.17 up to 87.5 μg mL-1 were tested against S. mutans. We diluted the exponential cultures in TSB and incubated them (37°C) in the presence of different γ-lactones or γ-lactams dilutions. Afterwards, we measured the planktonic growth by optical density at 630 nm and therefore assessed the biofilm density by the crystal violet staining method. Results Twelve compounds were active against biofilm formation, showing no effect on bacterial viability. Only one compound was inactive against both planktonic and biofilm growth. The highest biofilm inhibition (inhibition rate above 60%) was obtained for two compounds while three other compounds revealed an inhibition rate above 40%. Conclusions Twelve of the thirteen compounds revealed effective inhibition of S. mutans biofilm formation, with eight of them showing a specific antibiofilm effect. <![CDATA[Influence of <em>Helicobacter pylori</em> culture supernatant on the ecological balance of a dual-species oral biofilm]]> Abstract Dental caries is a chronic progressive disease occurring in the tooth hard tissue due to multiple factors, in which bacteria are the initial cause. Both Streptococcus mutans and Streptococcus sanguinis are main members of oral biofilm. Helicobacter pylori may also be detected in dental plaque, playing an important role in the development of dental caries. Objective The aim of this study was to investigate the effect of H. pylori culture supernatant on S. mutans and S. sanguinis dual-species biofilm and to evaluate its potential ability on affecting dental health. Material and methods The effect of H. pylori supernatant on single-species and dual-species biofilm was measured by colony forming units counting and fluorescence in situ hybridization (FISH) assay, respectively. The effect of H. pylori supernatant on S. mutans and S. sanguinis extracellular polysaccharides (EPS) production was measured by both confocal laser scanning microscopy observation and anthrone-sulfuric acid method. The effect of H. pylori supernatant on S. mutans gene expression was measured by quantitative real-time PCR (qRT-PCR) assays. Results H. pylori supernatant could inhibit both S. mutans and S. sanguinis biofilm formation and EPS production. S. sanguinis inhibition rate was significantly higher than that of S. mutans. Finally, S. mutans bacteriocin and acidogenicity related genes expression were affected by H. pylori culture supernatant. Conclusion Our results showed that H. pylori could destroy the balance between S. mutans and S. sanguinis in oral biofilm, creating an advantageous environment for S. mutans, which became the dominant bacteria, promoting the formation and development of dental caries. <![CDATA[The effects of IL-10 gene polymorphism on serum, and gingival crevicular fluid levels of IL-6 and IL-10 in chronic periodontitis]]> Abstract Objective Anti-inflammatory cytokines play a crucial role in periodontitis by inhibiting synthesis of pro-inflammatory cytokines. The purpose of this study was to evaluate the effect of interleukin-10 (-597) gene polymorphism and genotype distributions on chronic periodontitis (CP) development and IL-6 and IL-10 levels in gingival crevicular fluid (GCF) and serum before and after non-surgical periodontal treatment. Material and Methods The study population consisted of 55 severe generalized CP patients as CP group and 50 healthy individuals as control group. Plaque index, gingival index, probing depth and clinical attachment level were recorded and GCF and blood samples were taken at both the baseline and the sixth week after non-surgical periodontal treatment. PCR-RFLP procedure was used for gene analyses and cytokine levels were measured via ELISA. Results IL-10 genotype distribution was significantly different between CP and control groups (p=0.000, OR:7, 95%CI, 2.83-60.25). Clinical measurements significantly improved in the CP group after periodontal treatment (p&lt;0.05). Periodontal treatment significantly decreased GCF IL-6 and IL-10 levels. No significant difference was found in clinical parameters between IL-10 AA and AC+CC genotypes at both the baseline and the sixth week (p&gt;0.05). Sixth week GCF IL-10 levels were significantly lower in patients carrying IL-10 AC+CC genotype compared to the patients carrying IL-10 AA genotype (p&lt;0.05). Serum IL-6 and IL-10 levels were lower in patients carrying the IL-10 AA genotype compared to patients with IL-10 AC+CC genotype, but the difference was not significant (p&gt;0.05). Conclusion IL-10 AA genotype carriers had lower IL-6 and IL-6/10 levels in serum; however, GCF IL-6/10 levels were similar in both genotypes. Within the limitations of our study, a possible association between IL-10(-597) gene polymorphism and CP might be considered. <![CDATA[The value of fine needle aspiration cytology in the clinical management of rare salivary gland tumors]]> Abstract Salivary gland tumors are relatively rare neoplasms, mostly located in the parotid gland, and few are malignant. Preoperative evaluation of salivary gland tumors includes fine needle aspiration cytology (FNAC). Objective The purpose of this study was to determine the importance of FNAC in the evaluation of rare salivary gland neoplasms. Material and Methods Four cases of rare salivary gland tumors were included, which were preoperatively assessed by clinical investigation, computed tomography, and FNAC. Results The presented cases include myoepithelial carcinoma, oncocytic carcinoma, undifferentiated lymphoepithelial carcinoma, and marginal zone lymphoma. Conclusion FNAC is a reliable diagnostic tool for common salivary gland neoplasms; however, rare tumors often represent diagnostic challenges. Clinical relevance In such rare tumors, the role of aspiration cytology may be limited to establishing the dignity of the lesion (benign/malignant). This knowledge enables the surgeon to choose the most appropriate therapeutic procedure. A definitive diagnosis of rare tumors (either epithelial or nonepithelial) is obtained by histological examination; cytology is limited in this regard due to overlapping features. <![CDATA[Analysis of the antimicrobial and anti-caries effects of TiF<sub>4</sub> varnish under microcosm biofilm formed on enamel]]> Abstract Titanium tetrafluoride (TiF4) is known for interacting with enamel reducing demineralization. However, no information is available about its potential antimicrobial effect. Objectives This study evaluated the antimicrobial and anti-caries potential of TiF4 varnish compared to NaF varnish, chlorhexidine gel (positive control), placebo varnish and untreated (negative controls) using a dental microcosm biofilm model. Material and Methods A microcosm biofilm was produced on bovine enamel previously treated with the varnishes, using inoculum from human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. All experiments were performed in biological triplicate (n=4/group in each experiment). Factors evaluated were: bacterial viability (% dead and live bacteria); CFU counting (log10 CFU/mL); and enamel demineralization (transverse microradiography – TMR). Data were analysed using ANOVA/Tukey's test or Kruskal-Wallis/Dunn's test (p&lt;0.05). Results Only chlorhexidine significantly increased the number of dead bacteria (68.8±13.1% dead bacteria) compared to untreated control (48.9±16.1% dead bacteria). No treatment reduced the CFU counting (total microorganism and total streptococci) compared to the negative controls. Only TiF4 was able to reduce enamel demineralization (ΔZ 1110.7±803.2 vol% μm) compared to both negative controls (untreated: ΔZ 4455.3±1176.4 vol% μm). Conclusions TiF4 varnish has no relevant antimicrobial effect. Nevertheless, TiF4 varnish was effective in reducing enamel demineralization under this model. <![CDATA[Physicochemical properties of calcium silicate-based formulations MTA Repair HP and MTA Vitalcem]]> Abstract Objective This study aimed to analyze the following physicochemical properties: radiopacity, final setting time, calcium release, pH change, solubility, water sorption, porosity, surface morphology, and apatite-forming ability of two calcium silicate-based materials. Material and methods We tested MTA Repair HP and MTA Vitalcem in comparison with conventional MTA, analyzing radiopacity and final setting time. Water absorption, interconnected pores and apparent porosity were measured after 24-h immersion in deionized water at 37°C. Calcium and pH were tested up to 28 d in deionized water. We analyzed data using two-way ANOVA with Student-Newman-Keuls tests (p&lt;0.05). We performed morphological and chemical analyses of the material surfaces using ESEM/EDX after 28 d in HBSS. Results MTA Repair HP showed similar radiopacity to that of conventional MTA. All materials showed a marked alkalinizing activity within 3 h, which continued for 28 d. MTA Repair HP showed the highest calcium release at 28 d (p&lt;0.05). MTA Vitalcem showed statistically higher water sorption and solubility values (p&lt;0.05). All materials showed the ability to nucleate calcium phosphate on their surface after 28 d in HBSS. Conclusions MTA Repair HP and MTA Vitalcem had extended alkalinizing activity and calcium release that favored calcium phosphate nucleation. The presence of the plasticizer in MTA HP might increase its solubility and porosity. The radiopacifier calcium tungstate can be used to replace bismuth oxide. <![CDATA[Dynamics of the seasonal airborne propagation of <em>Staphylococcus aureus</em> in academic dental clinics]]> Abstract Objective Staphylococcus aureus strains can be disseminated during dental treatments and occasionally lead to the contamination and infection of patients and dentists, which is an important public health problem. The dynamics of the airborne propagation and the genetic diversity of S. aureus isolated in an academic dental clinic environment were investigated using isoenzyme typing. Material and Methods The isoenzymes of 44 previously reported isolates were obtained from fresh cultures and extracted using glass beads. Nine isoenzymes were investigated using multilocus enzyme electrophoresis (MLEE). The genetic diversity and relationship among the strains (electrophoretic type – ET) were determined using statistics previously described by Nei25 (1972) and the SAHN grouping method (UPGMA algorithm). Results Clonal pattern analyses indicated a high level of genetic polymorphism occurring among the 33 ETs, which were grouped into five taxa. Each taxon presented one or more clusters that were moderately related and that contained two or more identical/highly related isolates, revealing seasonal airborne propagation in these dental clinic environments. Conclusions These data suggest the occurrence of active microevolutionary processes in S. aureus as well as the possibility of environmental propagation during a 14-month time span. Such findings are important to show that multiuser academic dental clinics can retain certain strains that are spreadable to different niches. <![CDATA[The impact of nonsyndromic cleft lip with or without cleft palate on oral health-related quality of life]]> Abstract Nonsyndromic cleft lip with or without cleft palate (NSCL±P) compromises oral health, leading to missing or malformed teeth, and hampering oral hygiene. Apart from anatomic damages, NSCL±P also culminates in an impact on the routine quality of life with social privation and psychological embarrassment. Objective To evaluate the impact of NSCL±P on oral health-related quality of life. Material and Methods The study was classified as exploratory and descriptive, with quantitative approach. Patients with NSCL±P treated between August 2013 and September 2014 at the Cleft Lip and Palate Integral Care Center (CAIF), Curitiba, Brazil, were invited to participate. Age and sex-related data were collected, as well as level of education, financial income, type of orofacial cleft, use of orthodontic and prosthetic appliances, and number of previous orofacial surgeries. Selected patients were asked to answer the Oral Impact on Daily Performance (OIDP) questionnaire designed to measure the impact of oral health on daily performances. Results The sample was composed of 103 (44.59%) women and 128 (55.41%) men, with mean age of 19.74 ± 10.20 (7–65) years. The OIDP values ranged from 1 to 175 in 114 (49.35%) patients (mean: 22.38), whereas 117 patients (50.65%) presented total OIDP value equal to zero. High negative impact of NSCL±P on daily performances was detected when associated with the female sex (p=0.037). Daily performances related to phonetics (OIDP2; 2.63) and aesthetics (OIDP5; 2.48) presented the highest average values when compared to other daily performances, except OIDP6. The main symptoms and reported oral problems comprised the aesthetic dissatisfaction. Conclusions Almost half of the patients evaluated in this study showed negative impact of NSCL±P in the performance of daily activities. <![CDATA[Association between TNFα - 308 G/A polymorphism and oral lichen planus (OLP): a meta-analysis]]> Abstract Objectives To determine whether Tumor Necrosis Factor alpha (TNFα) –308 G/A polymorphism is associated with oral lichen planus (OLP). Material and Methods A systematic electronic search of the literature was conducted to identify all published studies on the association between TNFα –308 G/A polymorphism and OLP. All case-control studies evaluating the TNFα –308 G/A polymorphisms in OLP were selected. A meta-analysis of the studies that fulfilled the inclusion criteria was performed. Odds ratios (OR) with 95% confidence intervals (CI) were also calculated. Results Seven studies comprising 450 OLP cases and 867 controls were included in the meta-analysis. In the pooled analysis, TNFα –308 G/A polymorphism was associated with OLP with random effects and OR of 2.33 (95%CI=1.07-5.11; p=0.03), assuming a dominant mode of inheritance (AA+GA vs. GG). In the subgroup analysis by ethnicity, TNFα –308 G/A was associated with a significantly increased odds ratio of OLP in mixed ethnicity (OR=5.22; 95%CI=1.93-14.15; p=0.001), but not in Asians (OR=1.57; 95%CI=0.54-4.54; p=0.41) or Caucasians (OR=1.45; 95%CI=0.19-11.22; p=0.72). For subgroup analysis based on HCV (hepatitis C virus) infection status, significant increased risk of OLP was found among patients with mixed HCV infection status (OR=3.77; 95%CI=1.07-13.2; p=0.038), but not in patients without HCV infection (OR=2.09; 95%CI=0.63-6.91; p=0.22) and patients with HCV infection (OR=0.48; 95%CI=0.13-1.69; p=0.25). Conclusion Our results suggest that –308 G/A polymorphism in TNFα is a potential genetic marker for OLP. <![CDATA[The effect of periodontal therapy on neopterin and vascular cell adhesion molecule-1 levels in chronic periodontitis patients with and without acute myocardial infarction: a case-control study]]> Abstract The presence of neopterin in gingival crevicular fluid (GCF) is a marker for local and acute immune activation, and the presence of vascular cell adhesion molecule (VCAM-1) in GCF is accepted as a marker for chronic vascular inflammation. Objectives This study aimed to evaluate effects of periodontal treatment on GCF levels of neopterin and VCAM-1 in patients with chronic periodontitis (CP) with acute myocardial infarction (AMI) compared with systemically healthy CP patients. Material and methods Sixty subjects (20 CP patients with AMI, 20 healthy CP patients, and 20 healthy controls) were included. GCF samples were analyzed at baseline and after 3 and 6 months, and the probing pocket depth (PD), clinical attachment level (CAL), bleeding on probing, gingival (GI) and plaque (PI) indices were recorded. We determined neopterin and VCAM-1 levels (concentration and total amount) using enzyme-linked immunosorbent assay (ELISA). No significant differences were seen between the AMI+CP and CP groups for PI, GI, GCF levels of neopterin and VCAM-1 at baseline. Results The number of teeth with 5 mm≤CAL&lt;7 mm and CAL≥7 mm were significantly increased in the AMI+CP group at baseline. There were no significant differences between the AMI+CP and CP for PI, CAL, GCF volumes, and the AMI+CP group had the highest clinical improvement in the number of teeth with 5 mm≤CAL&lt;7 mm at the sixth month. There were significant positive correlations between clinical periodontal inflammation and the presence of neopterin and VCAM-1 in GCF prior to and following periodontal treatment, and between the GCF volume and clinical parameters. Conclusions Data suggest that the total amount and concentration of neopterin and VCAM-1 in GCF seemed to be closely associated with periodontal disease severity in CP patients with AMI. Moreover, the results of our study demonstrate that the past periodontal status is potentially correlated between groups, with similar periodontal disease severity. <![CDATA[Non-contact profilometry of eroded and abraded enamel irradiated with an Er:YAG laser]]> Abstract Literature has reported positive results regarding the use of lasers in the control of erosive lesions; however, evaluating whether they are effective in the control of the progression of erosive/abrasive lesions is important. Objectives This study aimed to evaluate the effect of the Er:YAG laser irradiation in controlling the progression of erosion associated with abrasive lesions in enamel. Material and methods Bovine incisors were sectioned, flattened and polished. Forty-eight enamel slabs were subjected to treatment in an intraoral phase. Twelve volunteers used an intraoral appliance containing one slab that was irradiated with an Er:YAG laser (5.2 J/cm2, 85 mJ, 2 Hz) and another non-irradiated slab on each side of the appliance, during one phase of 5 d, under a split-mouth design. Devices were subjected to erosive challenges (1% citric acid, 5 min, 3 times a day) and abrasive challenges one h after (brushing force of 1.5 N for 15 s) randomly and independently on each side of the device. Measurements of enamel loss were performed via 3D optical profilometry (μm). We analyzed data using the Kruskal-Wallis and Mann-Whitney tests and morphological characteristics via scanning electron microscopy. Results Following erosive and abrasive challenges, the group that was irradiated with the Er:YAG laser presented less loss of structure than the non-irradiated group. The group that underwent erosion and irradiation did not exhibit a significant difference from the non-irradiated group. Conclusion Irradiation with the Er:YAG laser did not control the loss of structure of enamel subjected to erosion but did control abrasion after erosion. <![CDATA[Doxycycline-containing glass ionomer cement for arresting residual caries: an <em>in vitro</em> study and a pilot trial]]> Abstract In a previous study, we demonstrated that the incorporation of doxycycline hyclate (DOX) into resin-modified glass ionomer cement (RMGIC) inhibited important cariogenic microorganisms, without modifying its biological and mechanical characteristics. In this study, we keep focused on the effect of that experimental material as a potential therapy for arresting residual caries by analyzing other in vitro properties and conducting a pilot clinical trial assessing the in vivo effect of DOX-containing RMGIC on residual mutans streptococci after partial carious removal in primary molars. Specimens of the groups RMGIC (control); RMGIC + 1.5% DOX; RMGIC + 3% DOX; and RMGIC + 4.5% DOX were made to evaluate the effect of DOX incorporation on surface microhardness and fluoride release of RMGIC and against biofilm of Streptococcus mutans. Clinical intervention consisted of partial caries removal comparing RMGIC and RMGIC + 4.5% DOX as lining materials. After 3 months, clinical and microbiologic evaluations were performed. Data were submitted to ANOVA/Tukey or Wilcoxon/Mann-Whitney set as α=0.05. Fluoride release and surface microhardness was not influenced by the incorporation of DOX (p&gt;0.05). There was a significant reduction of S. mutans biofilm over the material surface with the increase of DOX concentration. After clinical trial, the remaining dentin was hard and dry. Additionally, mutans streptococci were completely eliminated after 3 months of treatment with RMGIC + 4.5% DOX. The incorporation of DOX provided better antibiofilm effect, without jeopardizing fluoride release and surface microhardness of RMGIC. This combination also improved the in vivo shortterm microbiological effect of RMGIC after partial caries removal. <![CDATA[The maxillary lateral incisor in the rehabilitation of cleft lip and palate]]> Abstract Objective This study analyzed the maintenance of lateral incisors in the dental rehabilitation of individuals with cleft lip and palate. Material and Methods The study was conducted on a tertiary craniofacial center and comprised retrospective analysis of panoramic and periapical radiographs of Caucasoid individuals with non-syndromic complete unilateral cleft lip and palate, analyzing all radiographs available on the records of each individual, from the first to the last up to 12 years of age. Overall, 2,826 records were reviewed to achieve a sample of 1,000 individuals. Among these, 487 individuals presented the permanent lateral incisors on both cleft and non-cleft sides, which were included in this study. Results The results were evaluated in percentages and by descriptive statistics. The association between maintenance of the lateral incisor and timing of alveolar bone graft were analyzed by the t test. Among the 487 individuals, 265 had not completed treatment, 62 presented insufficient information, and 44 concluded the treatment elsewhere. Among the remaining 116 individuals, the lateral incisor was extracted from 88 (75.86%) of them on the cleft side (CS) and from 23 (19.83%) people on the non-cleft side (NCS). The age at accomplishment of alveolar bone graft was significantly associated with maintenance of the lateral incisor on the cleft side (p&lt;0.01). Most extractions were indicated because of the inadequate positioning on the CS and for midline correction on the NCS. Rehabilitation was primarily completed by orthodontic movement (53 individuals on the CS and 13 individuals on the NCS). Conclusion In conclusion, the lateral incisor on the cleft side was not maintained in most individuals. Positive relationship was observed between extraction of the lateral incisor and age at accomplishment of the alveolar bone graft, suggesting the need to anticipate the initial radiographic evaluation to enhance its maintenance and reduce the procedures required for rehabilitation. <![CDATA[Evaluation of photobiomodulation therapy associated with guided bone regeneration in critical size defects. <em>In vivo</em> study]]> Abstract The repair of bone defects raises the interest of investigators in several health specialties. Grafting techniques with bone substitutes and laser therapies have been investigated to replace autogenous bone and accelerate the bone healing process. Objective To evaluate the effect of photobiomodulation therapy (PBMT) associated with guided bone regeneration (GBR) in critical size defects. Material and Methods The study was conducted on 80 male rats (Rattus norvegicus albinus, Wistar) submitted to surgical creation of a critical size defect on the calvaria, divided into eight study groups: group C (control - only blood clot); group M (collagen membrane); group PBMT (photobiomodulation therapy); group AB (autogenous bone); group AB+PBMT; group AB+M; group PBMT+M; group AB+PBMT+M. The animals were killed 30 days postoperatively. After tissue processing, bone regeneration was evaluated by histomorphometric analysis and statistical analyses were performed (Tukey test, p&lt;0.05). Results All groups had greater area of newly formed bone compared to group C (9.96±4.49%). The group PBMT+M (achieved the greater quantity of new bone (64.09±7.62%), followed by groups PBMT (47.67±8.66%), M (47.43±15.73%), AB+PBMT (39.15±16.72%) and AB+PBMT+M (35.82±7.68%). After group C, the groups AB (25.10±16.59%) and AB+M (22.72±13.83%) had the smallest quantities of newly formed bone. The area of remaining particles did not have statistically significant difference between groups AB+M (14.93±8.92%) and AB+PBMT+M (14.76±6.58%). Conclusion The PBMT utilization may be effective for bone repair, when associated with bone regeneration techniques. <![CDATA[Chlorhexidine for prevention of alveolar osteitis: a randomised clinical trial]]> Abstract Objective To determine the effectiveness of chlorhexidine 0.12% mouthwash (CHX) after tooth extraction for the prevention of alveolar osteitis (AO). Material and methods We conducted a double-blind randomised clinical trial stratified by risk factors. We enrolled a cohort of 822 patients who underwent dental extractions, and were considered to be at risk of developing AO (previous surgical site infection, traumatic extraction, and tobacco smoking). After extraction, patients were randomly allocated for CHX group or placebo group, matched by risk factors. The primary outcome was clinical diagnosis of AO: increasing postoperative pain for 4 d within and around the socket, and total or partial breakdown of the blood clot in the socket with or without bone exposure. Results Follow-up was completed by 744 participants (372 chlorhexidine and 372 placebo). We detected no significant differences between the two groups at baseline. After completed follow-up, risk factors were equally distributed between the two groups. Overall incidence of OA was 4.97%, in which 27 participants treated with placebo (7.26%) and 10 participants treated with CHX (2.69%) developed AO. CHX reduced the incidence of AO by 63% [Absolute Risk Reduction: 4.57 (95% CI 1.5-7.7), Number Needed to Treat: 21.88 (95% CI 13.0-69.3), Fisher's exact test: p=0.006]. No adverse effects were reported. Conclusion The use of chlorhexidine 0.12% mouthwash after tooth extraction is safe and effective in reducing the incidence of AO in high-risk patients. <![CDATA[Model resin composites incorporating ZnO-NP: activity against S. <em>mutans</em> and physicochemical properties characterization]]> Abstract Although resin composites are widely used in the clinical practice, the development of recurrent caries at composite-tooth interface still remains as one of the principal shortcomings to be overcome in this field. Objectives To evaluate the activity against S. mutans biofilm of model resin composites incorporating different concentrations of ZnO-nanoparticles (ZnO-NP) and characterize their physicochemical properties. Materials and Methods Different concentrations of ZnO-NP (wt.%): E1=0, E2=0.5, E3=1, E4=2, E5=5 and E6=10 were incorporated into a model resin composite consisting of Bis-GMA-TEGDMA and barium borosilicate particles. The activity against S. mutans biofilm was evaluated by metabolic activity and lactic acid production. The following physicochemical properties were characterized: degree of conversion (DC%), flexural strength (FS), elastic modulus (EM), hardness (KHN), water sorption (Wsp), water solubility (Wsl) and translucency (TP). Results E3, E4, E5 and E6 decreased the biofilm metabolic activity and E5 and E6 decreased the lactic acid production (p&lt;0.05). E6 presented the lowest DC% (p&lt;0.05). No significant difference in FS and EM was found for all resin composites (p&gt;0.05). E5 and E6 presented the lowest values of KHN (p&lt;0.05). E6 presented a higher Wsp than E1 (p&lt;0.05) and the highest Wsl (p&lt;0.05). The translucency significantly decreased as the ZnO- NP concentration increased (p&lt;0.05). Conclusions The incorporation of 2 – 5 wt.% of ZnO-NP could endow antibacterial activity to resin composites, without jeopardizing their physicochemical properties. <![CDATA[Neurosensory analysis of tooth sensitivity during at-home dental bleaching: a randomized clinical trial]]> Abstract Objective The objective of this study was to evaluate dental sensitivity using visual analogue scale, a Computerized Visual Analogue Scale (CoVAS) and a neurosensory analyzer (TSA II) during at-home bleaching with 10% carbamide peroxide, with and without potassium oxalate. Materials and Methods Power Bleaching 10% containing potassium oxalate was used on one maxillary hemi-arch of the 25 volunteers, and Opalescence 10% was used on the opposite hemi-arch. Bleaching agents were used daily for 3 weeks. Analysis was performed before treatment, 24 hours later, 7, 14, and 21 days after the start of the treatment, and 7 days after its conclusion. The spontaneous tooth sensitivity was evaluated using the visual analogue scale and the sensitivity caused by a continuous 0°C stimulus was analyzed using CoVAS. The cold sensation threshold was also analyzed using the TSA II. The temperatures obtained were statistically analyzed using ANOVA and Tukey's test (α=5%). Results The data obtained with the other methods were also analyzed. 24 hours, 7 and 14 days before the beginning of the treatment, over 20% of the teeth presented spontaneous sensitivity, the normal condition was restored after the end of the treatment. Regarding the cold sensation temperatures, both products sensitized the teeth (p&lt;0.05) and no differences were detected between the products in each period (p&gt;0.05). In addition, when they were compared using CoVAS, Power Bleaching caused the highest levels of sensitivity in all study periods, with the exception of the 14th day of treatment. Conclusion We concluded that the bleaching treatment sensitized the teeth and the product with potassium oxalate was not able to modulate tooth sensitivity. <![CDATA[Evaluation of cases of concussion and subluxation in the permanent dentition: a retrospective study]]> Abstract Objectives This study evaluated the evolution of cases of concussion and subluxation through a retrospective study of 20 years. Material and Methods Were examined clinical and radiographic records of 1,309 patients who underwent treatment of dentoalveolar trauma in the discipline of Integrated Clinic of the School of Dentistry of Araçatuba, UNESP, of which we selected 137 whose patients had concussion and subluxation injuries, with average age of 23.3 (SD – 10.96). The variables collected were: gender, age, history of previous and actual trauma, treatments performed, the presence of necrotic pulp, and time elapsed until the same trauma. The concussion and subluxation groups were subjected to statistical analyses using the SPSS 16.0 version software (α=0.05), Chi-square, and t-tests. Results Of the 301 teeth involved, 49 (16.3%) suffered concussion and 252 (83.7%), subluxation, being the upper anterior teeth the most affected (75.1%) for both conditions. Subluxation and concussion traumas were more prevalent in men aged 10 to 20 years, most caused by cycling accidents (36.2%). There was a concomitant presence of crown fracture in 21% of cases of concussion and 34.7% of subluxation. Pulp necrosis was detected in 16.3% (concussion) and 27.1% (subluxation) (p=0.12), and most occurred within 6 months after the trauma (p=0.29). The pulp necrosis shows a positive correlation with motorcycle accidents (p=0.01), direct impact (p≤0.0001), crown fracture with pulp exposure (p≤0.0001), darkening of the crown (p=0.004) and spontaneous pain (p≤0.0001); and negative correlation with indirect impact (p≤0.0001). Conclusions Although concussion and subluxation traumas are considered of minor degrees, they must be monitored, since the possibility of pulp necrosis exists, and its early treatment favors a good prognosis. <![CDATA[Assessment of spontaneous resolution of idiopathic bone cavity]]> Abstract Idiopathic Bone Cavity (IBC) or Simple Bone Cyst (SBC) is a non- epithelialized bone cavity with serosanguinous fluid content or empty. There is a literature debate regarding its pathogenesis that remains unclear. The main treatment option is the surgical exploration, although there are successful cases described in the literature in which just a follow-up with clinical and radiographic evaluation was performed. Objective This study aimed to assess the spontaneous resolution of idiopathic bone cavity untreated by surgery. Material and Methods Twenty-one patients diagnosed with surgically untreated IBC were submitted to a follow-up protocol modified from Damante, Guerra, and Ferreira5 (2002). A clinical and radiographic evaluation was performed in 13 patients (13/21), while eight patients (8/21) were only radiographically evaluated. Three observers evaluated the panoramic radiographs of 21 patients and the Kappa test was performed by intra and inter-examiners. Inductive and descriptive statistics were applied to the results. Results Only one patient had a positive response to palpation and percussion of the teeth in the cyst area. Most of the cysts evaluated were rated as 3 (lesion “in involution”), 4 (lesion “almost completely resolved”), or 5 (“completely resolved”). Conclusions We observed progressive spontaneous resolution of IBC. Most cysts were found in the recovery process in different follow-up periods. Patient's follow-up, without surgery, may be considered after the diagnosis based on epidemiological, clinical, and radiographic features of the lesion. <![CDATA[Influence of remaining coronal thickness and height on biomechanical behavior of endodontically treated teeth: survival rates, load to fracture and finite element analysis]]> Abstract Objective To evaluate the effect of restorative strategy (fiber post vs cast post and core), coronal height (0 mm vs 2 mm) and thickness (higher than 1 mm vs lower than 1 mm) on survival rate, fracture resistance and stress distribution. Material and Methods Seventy-two bovine teeth were cleaned and allocated in six groups (n = 12). Twenty-four teeth were sectioned at 13 mm length (no remaining coronal structure) and forty-eight were sectioned at 15 mm (2 mm remaining coronal structure). Half of the forty-eight had remaining coronal thickness lower than 1 mm and the other half had thickness higher than 1 mm. All root canals were prepared at 10 mm (luting length), fiber posts were cemented in thirty-six specimens and cast post and core in other thirty-six. All teeth were restored with metallic crowns. Specimens were submitted to 1.5 million cycles (100 N, 45°, 10 Hz at 2 mm below incisal edge) and evaluated at each 500,000 cycles to detect failures. Specimens that survived were submitted to load to fracture test. Bidimensional (Rhinoceros® 4.0) models were obteined survival data submitted to Kaplan-Meier (α=0.05) analysis and load to fracture values submitted to ANOVA and Tukey tests (α=0.05). Results Groups without remaining coronal structure showed survival rates lower than other groups (p=0.001). ANOVA showed higher values of load to fracture for groups with coronal thickness higher than 1 mm (p=0.0043). Finite element analysis showed better stress distribution in groups with remaining coronal structure and restored with fiber post. Conclusion Specimens without remaining coronal structure have lower survival rates. Specimens with remaining structure lower than 1 mm and without coronal structure support the same load to fracture value independently of the restorative strategy. <![CDATA[Circulation levels of acute phase proteins pentraxin 3 and serum amyloid A in atherosclerosis have correlations with periodontal inflamed surface area]]> Abstract Objectives One of the plausible mechanisms in the relationship between periodontitis and coronary artery disease (CAD) is the systemic inflammatory burden comprised of circulating cytokines/mediators related to periodontitis. This study aims to test the hypothesis that periodontal inflamed surface area (PISA) is correlated with higher circulating levels of acute phase reactants (APR) and pro-inflammatory cytokines/mediators and lower anti-inflammatory cytokines/mediators in CAD patients. Material and Methods Patients aged from 30 to 75 years who underwent coronary angiography with CAD suspicion were included. Clinical periodontal parameters (probing depth - PD, clinical attachment loss, and bleeding on probing - BOP) were previously recorded and participants were divided into four groups after coronary angiography: Group 1: CAD (+) with periodontitis (n=20); Group 2: CAD (+) without periodontitis (n=20); Group 3: CAD (-) with periodontitis (n=21); Group 4: CAD (-) without periodontitis (n = 16). Serum interleukin (IL) −1, −6, −10, tumor necrosis factor (TNF)-α, serum amyloid A (SAA), pentraxin (PTX) 3, and high-sensitivity C-reactive protein (hs-CRP) levels were measured with ELISA. Results Groups 1 and 3 showed periodontal parameter values higher than Groups 2 and 4 (p&lt;0.0125). None of the investigated serum parameters were statistically significantly different between the study groups (p&gt;0.0125). In CAD (-) groups (Groups 3 and 4), PISA has shown positive correlations with PTX3 and SAA (p&lt;0.05). Age was found to predict CAD significantly according to the results of the multivariate regression analysis (Odds Ratio: 1.17; 95% Confidence Interval: 1.08-1.27; p&lt;0.001). Conclusions Although age was found to predict CAD significantly, the positive correlations between PISA and APR in CAD (-) groups deserve further attention, which might depend on the higher PISA values of periodontitis patients. In further studies conducted in a larger population, the stratification of age groups would provide us more accurate results. <![CDATA[A SERM increasing the expression of the osteoblastogenesis and mineralization-related proteins and improving quality of bone tissue in an experimental model of osteoporosis]]> Abstract Raloxifene is an antiresorptive drug, selective estrogen receptor modulator (SERM) used in the treatment of osteoporosis. Objective To evaluate proteins related to bone repair at the peri-implant bone in a rat model of osteoporosis treated with raloxifene. Material and Methods 72 rats were divided into three groups: SHAM (healthy animals), OVX (ovariectomized animals), and RLX (ovariectomized animals treated with raloxifene). Raloxifene was administered by gavage (1 mg/kg/day). Tibial implantation was performed 30 days after ovariectomy, and animals were euthanized at 14, 42, and 60 days postoperatively. Samples were collected and analyzed by immunohistochemical reactions, molecular analysis, and microtomographic parameters. Results RLX showed intense staining of all investigated proteins at both time points except for RUNX2. These results were similar to SHAM and opposite to OVX, showing mild staining. The PCR gene expression of OC and ALP values for RLX (P&lt;0.05) followed by SHAM and OVX groups. For BSP data, the highest expression was observed in the RLX groups and the lowest expression was observed in the OVX groups (P&lt;0.05). For RUNX2 data, RLX and SHAM groups showed greater values compared to OVX (P&lt;0.05). At 60 days postoperatively, microtomography parameters, related to closed porosity, showed higher values for (Po.N), (Po.V), and (Po) in RLX and SHAM groups, whereas OVX groups showed lower results (P&lt;0.05); (BV) values (P=0.009); regarding total porosity (Po.tot), RLX group had statistically significant lower values than OVX and SHAM groups (P=0.009). Regarding the open porosity (Po.V and Po), the SHAM group presented the highest values, followed by OVX and RLX groups (P&lt;0.05). The Structural Model Index (SMI), RLX group showed a value closer to zero than SHAM group (P&lt;0.05). Conclusions Raloxifene had a positive effect on the expression of osteoblastogenesis/mineralization-related proteins and on micro-CT parameters related to peri-implant bone healing. <![CDATA[Effects of three silane primers and five adhesive agents on the bond strength of composite material for a computer-aided design and manufacturing system]]> Abstract Objective The objective of this study was to evaluate the effects of combinations of silane primers and adhesive agents on the bond strength of a composite block for a computer-aided design and manufacturing system. Material and Methods Three silane primers [Clearfil Ceramic Primer (CP), Super-Bond PZ Primer (PZ), and GC Ceramic Primer II (GP)] were used in conjunction with five adhesive agents [G-Premio Bond (P-Bond), Repair Adhe Adhesive (R-Adhesive), Super-Bond D-Liner Dual (SB-Dual), Super-Bond C&amp;B (SB-Self), and SB-Dual without tributylborane derivative (SB-Light)]. The surface of a composite block (Gradia Block) was ground with silicon carbide paper. After treatment with a silane primer, a adhesive agent was applied to each testing specimen. The specimens were then bonded with a light-curing resin composite. After 24 h, the shear bond strength values were determined and compared using a post hoc test (α=0.05, n=8/group). We also prepared control specimens without primer (No primer) and/or without adhesive agent (No adhesive). Results PZ/SB-Dual and GP/SB-Dual presented the highest bond strength, followed by GP/P-Bond, CP/SB-Dual, CP/R-Adhesive, No primer/SB-Dual, GP/R-Adhesive, CP/P-Bond, No primer/R-Adhesive, PZ/R-Adhesive, CP/SB-Self, PZ/P-Bond, PZ/SB-Self, and GP/SB-Self in descending order of bond strength. No primer/P-Bond, No primer/SB-Self, and all specimens in the SB-Light and No adhesive groups presented the lowest bond strengths. Conclusion A dual-curing adhesive agent (SB-Dual) containing a tributylborane derivative in combination with a silane primer (GP or PZ) presents a greater bond strength between the composite block and the repairing resin composite than the comparators used in the study. <![CDATA[Porosity, water sorption and solubility of denture base acrylic resins polymerized conventionally or in microwave]]> Abstract The proper selection of polymerization cycle is important to prevent overheating of the monomer that could cause degradation, porosity and, consequently, deleterious effects on the denture base properties. Objective This study evaluated the porosity, water sorption and solubility of acrylic resins (Vipi Cril-VC and Vipi Wave-VW) after conventional or microwave polymerization cycles. Material and Methods Specimens (n = 10) were made and cured: 1-WB = 65°C during 90 min + boiling during 90 min (VC cycle - control group); 2-M25 = 10 min at 270 W + 5 min at 0 W + 10 min at 360 W (VW cycle); 3-M3 = 3 min at 550 W; and 4-M5 = 5 min at 650 W. Afterward, they were polished and dried in a dessicator until a constant mass was reached. Specimens were then immersed in distilled water at 37°C and weighed regularly until a constant mass was achieved. For porosity, an additional weight was made with the specimen immediately immersed in distilled water. For water sorption and solubility, the specimens were dried again until equilibrium was reached. Data were submitted to 2 way-ANOVA and Tukey HSD (α=0.05). Results Porosity mean values below 1.52% with no significant difference among groups for both materials were observed. Resins showed water sorption and solubility values without a significant difference. However, there was a significant difference among groups for these both properties (P&lt;0.013). The highest sorption (2.43%) and solubility (0.13%) values were obtained for WB and M3, respectively. Conclusions The conventional acrylic resin could be polymerized in a microwave since both the materials showed similar performance in the evaluated properties. Shorter microwave cycles could be used for both the materials without any detectable increase in volume porosity. <![CDATA[Immediate effects of temporary bite-raising with light-cured orthodontic band cement on the electromyographic response of masticatory muscles]]> Abstract Objective: To assess the immediate effects of temporary bite-raising using light-cured orthodontic band cement on the superficial masseter and anterior temporalis electromyography (EMG) activity in healthy adults. Materials and Methods: Surface EMG signals were recorded bilaterally from the superficial masseter and anterior temporalis muscles of 30 volunteers with a normal occlusion, before and after having temporary bite-raising. The bite-raising was done by adding light-cured orthodontic band cement (3x5x2 mm WxLxH) on the lingual cusps of both upper first molars. The measurements were recorded (i) at rest, (ii) while clenching in centric occluding position and (iii) while chewing on an artificial test food. The EMG activity at rest and during clenching, the maximum voltage, and the duration of the identified EMG signal burst while chewing the artificial test food before and after temporary bite-raising were statistically compared using the paired t-test or the Wilcoxon signed-rank test based on the normality of the variables. The significance level was set at 5%. Results: After temporary bite-raising, we found no significant change in integral EMG activity at rest position for the superficial masseter (mean difference (MD)=7.5 μVs) and for the anterior temporalis muscle (MD=36.8 μVs); however, the integral EMG activity during clenching was significantly reduced for the superficial masseter (MD=201.2 μVs) and for the anterior temporalis muscle (MD=151.8 μVs). During mastication, the maximum voltage of the identified burst was significantly reduced on the preferred chewing side of the superficial masseter and anterior temporalis muscles (MD=127.9 and 47.7 μV, respectively), while no significant change was found for the duration of the identified burst (MD=-34.1 and 3.4 ms, respectively) after temporary bite-raising. Conclusion: The results point to an altered neuromuscular behavior during clenching and chewing immediately after temporary bite-raising with light-cured orthodontic band cement. This information is relevant for orthodontists to inform their patients what will happen to their masticatory muscle activity when this bite-raising method is used. <![CDATA[TiF<sub>4</sub> varnish protects the retention of brackets to enamel after <em>in vitro</em> mild erosive challenge]]> Abstract The effect of fluoride agents on the retention of orthodontic brackets to enamel under erosive challenge is little investigated. Objective: The aim of this study was to evaluate the effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) agents on the shear bond strength of brackets to enamel and on the enamel microhardness around brackets under erosive challenge. Methods: Brackets were bonded to bovine incisors. Five groups were formed according to fluoride application (n=10): TiF4 varnish, TiF4 solution, NaF varnish, NaF solution and control (without application). The specimens were submitted to erosive challenge (90 s cola drink/2h artificial saliva, 4x per day for 7 days). Solutions were applied before each erosive cycle and varnishes were applied once. Vickers Microhardness (VHN) was obtained before and after all cycles of erosion and the percentage of microhardness loss was calculated. Shear bond strength, adhesive remnant index and polarized light microscopy were conducted after erosion. The data were analyzed by ANOVA, Tukey, Kruskal-Wallis and Mann-Whitney U tests (α=0.05). Results: The %VHN had no statistically significant differences among the experimental groups. However, considering the comparisons of all groups with the control group, TiF4 varnish showed the highest protection from enamel demineralization (effect size of 2.94, while the effect size for the other groups was &gt;2.4). The TiF4 varnish group had significantly higher shear bond strength compared to other groups. There was no difference among groups for adhesive remnant index. Polarized light microscopy showed higher demineralization depth for the control group. Conclusions: Application of NaF and TiF4 agents during mild erosive challenge minimized the enamel mineral loss around brackets, however only the experimental TiF4 varnish was able to prevent the reduction of shear bond strength of brackets to enamel. <![CDATA[Extracellular calcium increases fibroblast growth factor 2 gene expression via extracellular signal-regulated kinase 1/2 and protein kinase A signaling in mouse dental papilla cells]]> Abstract We previously reported that elevated extracellular calcium (Ca2+) levels increase bone morphogenetic protein 2 expression in human dental pulp (hDP) cells. However, it is unknown whether extracellular Ca2+ affects the expression of other growth factors such as fibroblast growth factor 2 (FGF2). Objective: The present study aimed to examine the effect of extracellular Ca2+ on FGF2 gene expression in hDP and immortalized mouse dental papilla (mDP) cells. Materials and Methods: Cells were stimulated with 10 mM CaCl2 in the presence or absence of cell signaling inhibitors. FGF2 gene expression was assessed using real-time polymerase chain reaction. The phosphorylation status of signaling molecules was examined by Western blotting. Results: Extracellular Ca2+ increased FGF2 gene expression in mDP and hDP cells. Gene expression of the calcium-sensing receptor and G protein-coupled receptor family C group 6 member A, both of which are extracellular Ca2+ sensors, was not detected. Ca2+-mediated Fgf2 expression was reduced by pretreatment with the protein kinase A (PKA) inhibitor H-89 or extracellular signal-regulated kinase (ERK) 1/2 inhibitor PD98059 but not by pretreatment with the protein kinase C inhibitor GF-109203X or p38 inhibitor SB203580. Extracellular Ca2+ increased PKA activity and ERK1/2 phosphorylation. Ca2+-induced PKA activity decreased by pretreatment with PD98059. Conclusions: These findings indicate that elevated extracellular Ca2+ levels led to increased Fgf2 expression through ERK1/2 and PKA in mDP cells and that this mechanism may be useful for designing regenerative therapies for dentin. <![CDATA[Evaluation of the effect of dose-dependent platelet-rich fibrin membrane on treatment of gingival recession: a randomized, controlled clinical trial]]> Abstract Miller's class I gingival recessions (GR) have been treated using coronally advanced flap (CAF) with platelet-rich fibrin membrane (PRF membrane) or connective tissue graft (CTG). Objective: The aim of this study was to evaluate the effect of different multiple layers of PRF membranes for the treatment of GR compared with the CTG procedure. Material and Methods: Sixty-three Miller class I GR were treated in this study. Twenty-one GR selected randomly were treated with two layers of PRF membranes+CAF in 2PRF+CAF (test group-1), four layers of PRF membranes+CAF in 4PRF+CAF (test group-2), and CTG+CAF in the control group. The plaque index (PI), gingival index (GI), probing depth (PD), keratinized tissue thickness (KTT), clinical attachment level (CAL), recession depth (RD), recession width (RW), and keratinized tissue height (KTH) measurements were performed at baseline and 1, 3, and 6 months after surgery. The post-operative discomfort of patients, assessed with the visual analog scale (VAS) and healing index (HI), was recorded after surgery. Results: PI, GI, and PD scores were similar for all patients at all times. RD and RW scores were similar for each patient at 1 month, but these values were significantly increased in the subsequent periods in test group-1. The increase in KTT was significantly higher in the control group compared with the test groups. Similar root coverage scores were obtained in the test group-2 and control groups, and these scores were significantly higher compared with test group-1. Conclusions: The PRF membrane+CAF technique may be an alternative to the CTG+CAF technique for postoperative patient comfort. However, PRF membranes should use as many layers as possible. <![CDATA[Effects of a food enriched with probiotics on <em>Streptococcus mutans</em> and <em>Lactobacillus</em> spp. salivary counts in preschool children: a cluster randomized trial]]> Abstract Probiotics have provided benefits to general health, but they are still insufficient to dental health. Objective: This study aimed to evaluate milk supplemented with probiotic bacteria and standard milk, measured by levels of Streptococcus mutans (S. mutans) and Lactobacillus spp., in 3-4-year-old children after 9 months of intervention. Material and Methods: The study was a triple-blind, placebo-controlled, randomized trial. The sample was composed of 363 preschoolers attending five child development centers in Cali, Colombia. They were randomized to two groups: children in the intervention group drank 200 mL of milk with Lactobacillus rhamnosus 5x106 and Bifidobacteruim longum 3x106, and children in the control group drank 200 mL of standard milk. Interventions occurred on weekdays and information was gathered through scheduled clinical examination. The primary result was the number of colony forming units (CFU) of S. mutans and Lactobacillus spp. in the saliva. Secondary results were dental caries, rated by the International Caries Detection and Assessment System (ICDAS), dental plaque, pH, and salivary buffer capacity. Results: The proportion of S. mutans was lower in the intervention group compared with the control group after 9 months; however, the differences did not reach statistical significance (p=0.173); on the other hand, statistically significant differences between groups were found in the CFU/mL of Lactobacillus spp. (p=0.002). There was not statistically significant difference in the prevalence of dental caries for both groups (p=0.767). Differences between groups were found in the salivary buffering capacity (p=0.000); neither salivary pH nor dental plaque were significantly different. Conclusions: Regular consumption of milk containing probiotics bacteria reduced CFU/mL of Lactobacillus spp. and increased salivary buffering capacity at 9 months of consumption. <![CDATA[Osteoradionecrosis of the jaws: case series treated with adjuvant low-level laser therapy and antimicrobial photodynamic therapy]]> Abstract Background: Osteoradionecrosis of the jaw (ORNJ) is the most severe and complex sequel of head and neck radiotherapy (RT) because of the bone involved, it may cause pain, paresthesia, foul odor, fistulae with suppuration, need for extra oral communication and pathological fracture. We treated twenty lesions of ORNJ using low-level laser therapy (LLLT) and antimicrobial photodynamic therapy (aPDT). The objective of this study was to stimulate the affected area to homeostasis and to promote the healing of the oral mucosa. Methods: We performed aPDT on the exposed bone, while LLLT was performed around the bone exposure (red spectrum) and on the affected jaw (infrared spectrum). Monitoring and clinical intervention occurred weekly or biweekly for 2 years. Results: 100% of the sample presented clinical improvement, and 80% presented complete covering of the bone exposure by intact oral mucosa. Conclusion: LLLT and aPDT showed positive results as an adjuvant therapy to treat ORNJ. <![CDATA[Assessing the association between hypoxia during craniofacial development and oral clefts]]> Abstract Objectives To evaluate the association between hypoxia during embryo development and oral clefts in an animal model, and to evaluate the association between polymorphisms in the HIF-1A gene with oral clefts in human families. Material and Methods The study with the animal model used zebrafish embryos at 8 hours post-fertilization submitted to 30% and 50% hypoxia for 24 hours. At 5 days post-fertilization, the larvae were fixed. The cartilage structures were stained to evaluate craniofacial phenotypes. The family-based association study included 148 Brazilian nuclear families with oral clefts. The association between the genetic polymorphisms rs2301113 and rs2057482 in HIF-1A with oral clefts was tested. We used real time PCR genotyping approach. ANOVA with Tukey's post-test was used to compare means. The transmission/disequilibrium test was used to analyze the distortion of the inheritance of alleles from parents to their affected offspring. Results For the hypoxic animal model, the anterior portion of the ethmoid plate presented a gap in the anterior edge, forming a cleft. The hypoxia level was associated with the severity of the phenotype (p&lt;0.0001). For the families, there was no under-transmitted allele among the affected progeny (p&gt;0.05). Conclusion Hypoxia is involved in the oral cleft etiology, however, polymorphisms in HIF-1A are not associated with oral clefts in humans. <![CDATA[Immunohistological study of the effect of vascular Endothelial Growth Factor on the angiogenesis of mature root canals in rat molars]]> Abstract Tissue bioengineering has been applied to Endodontics to seek a more biological treatment. The presence of blood vessels is crucial for cell nutrition during tissue formation. Objective This study analysed the application of vascular endothelial growth factor (VEGF) in the angiogenesis of mature root canals. Material and methods Upper first molars of twelve 13-week old Wistar male rats were used. The root pulp of the mesiobuccal canal was removed and the root canal instrumented with K-files up to size #25. Periapical bleeding was induced into the root canal by introducing a #15 K-file beyond the apex. The teeth on the right side of the arch were filled up with blood clot (G1), whereas those on the left side were filled up with blood clot plus 50 ng/ml of VEGF (G2). Teeth were sealed with light-curing glass-ionomer cement and the animals were sacrificed after 60 days. The maxilla was dissected and fixed before obtaining serial sections for histological processing with haematoxylin-eosin (HE) and immunohistochemical factor-VIII. Immunohistochemical labelling was evaluated using scores for statistical analysis. Results Immunohistological analysis demonstrated the presence of angiogenesis in both groups, but with higher angiogenic maturation in G2 during the experimental period (p&lt;0.05). HE staining showed connective tissue with absence of odontoblasts in all specimens. Conclusions It can be concluded that it is possible to obtain angiogenesis in mature root canals with or without the use of VEGF, although the latter tends to accelerate blood vessel formation. <![CDATA[Cytidine-phosphate-guanosine oligodeoxynucleotides in combination with CD40 ligand decrease periodontal inflammation and alveolar bone loss in a TLR9-independent manner]]> Abstract Local administration of toll-like receptor 9 (TLR9), agonist cytidine-phosphate-guanosine oligodeoxynucleotide (CpG ODNs), and CD40 ligand (CD40L) can decrease ligature-induced periodontal inflammation and bone loss in wild type (WT) mouse. Objective: This study aimed to explore whether such effect is dependent on TLR9 signaling. Material and Methods: Purified spleen B cells isolated from WT C57BL/6J mice and TLR9 knockout (KO) mice were cultured for 48 hours under the following conditions: CD40L, CpG+CD40L, CpG at low, medium and high doses. We determined B cell numbers using a hemocytometer at 24 h and 48 h. Percentages of CD1dhiCD5+ B cells were detected by flow cytometry. Interleukin-10 (IL-10) mRNA expression and protein secretion were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and by ELISA, respectively. The silk ligature was tied around the maxillary second molars for 14 days, during which the CpG+CD40L mixture or PBS was injected into palatal gingiva on days 3, 6, and 9. Results: For both WT and TLR9 KO mice, CpG significantly induced B cell proliferation, increased IL-10 mRNA expression and protein secretion of IL-10 but reduced CD1dhiCD5+ B cells population; local injection of CpG+CD40L mixture significantly decreased alveolar bone loss and the number of TRAP-positive cells adjacent to the alveolar bone surface, and significantly increased the gingival mRNA expression of IL-10 and decreased RANKL and IFN-γ mRNA expression. Conclusions: These results indicated that CpG plus CD40L decreased periodontal inflammation and alveolar bone loss in a TLR9-independent manner in ligature-induced experimental periodontitis. <![CDATA[Solubility, porosity and fluid uptake of calcium silicate-based cements]]> Abstract Objective: To evaluate the absorption/fluid uptake, solubility and porosity of White mineral trioxide aggregate (MTA) Angelus, Biodentine (BIO), and zinc oxide-eugenol (ZOE). Material and Methods: Solubility was evaluated after immersion in distilled water for 7 and 30 days. Porosity was evaluated using digital inverted microscope, scanning electron microscope (SEM) and micro-computed tomography (micro-CT). For the fluid uptake test, specimens were immersed in Hank's balanced salt solution (HBSS) for 1, 7, 14 and 28 days. Fluid absorption, solubility and porosity of the materials were measured after each period. Statistical evaluation was performed using one-way analysis of variance (ANOVA) and Tukey tests, with a significance level at 5%. Results: After 7 and 30 days, BIO showed the highest solubility (p&lt;0.05). All methods demonstrated that MTA had total porosity higher than BIO and ZOE (p&lt;0.05). Micro-CT analysis showed that MTA had the highest porosity at the initial period, after its setting time (p&lt;0.05). After 7 and 30 days, ZOE had porosity lower than MTA and BIO (p&lt;0.05). Absorption was similar among the materials (p&gt;0.05), and higher fluid uptake and solubility were observed for MTA in the fluid uptake test (p&lt;0.05). Conclusions: BIO had the highest solubility in the conventional test and MTA had higher porosity and fluid uptake. ZOE had lower values of solubility, porosity and fluid uptake. Solubility, porosity and fluid uptake are related, and the tests used provided complementary data. <![CDATA[Bioactive glass added to autogenous bone graft in maxillary sinus augmentation: a prospective histomorphometric, immunohistochemical, and bone graft resorption assessment]]> Abstract Objective The aim of this study was to compare the bone resorption rate, histomorphometry and immunohistochemical findings of bioactive glass (Biogran; Biomet, Warsaw, IN, USA) mixed with autogenous bone grafts (1:1) and autogenous bone graft isolate in maxillary sinus elevation surgery. Material and Methods A total of 9 maxillary sinuses were grafted with Biogran with autogenous bone graft (group 1) and 12 were mixed with autogenous bone graft (group 2). Postoperative cone beam computed tomography (CBCT) was used to measure the initial graft volume after 15 days (T1), and 6 months later, another CBCT scan was performed to evaluate the final graft volume (T2) and determine the graft resorption rate. The resorption outcomes were 37.9%±18.9% in group 1 and 45.7%±18.5% in group 2 (P=0.82). After 6 months, biopsies were obtained concurrent with the placement of dental implants; these implants were subjected to histomorphometric analysis and immunohistochemical analysis for tartrate-resistant acid phosphatase (TRAP). Results The average bone formation in group 1 was 36.6%±12.9 in the pristine bone region, 33.2%±13.3 in the intermediate region, and 45.8%±13.8 in the apical region; in group 2, the values were 34.4%±14.4, 35.0%±13.9, and 42.0%±16.6 of new bone formation in the pristine bone, intermediate, and apical regions, respectively. Immunostaining for TRAP showed poor clastic activity in both groups, which can indicate that those were in the remodeling phase. Conclusions The similarity between the groups in the formation and maintenance of the graft volume after 6 months suggests that the bioactive glass mixed with autogenous bone (1:1) can be used safely as a bone substitute for the maxillary sinus lift. <![CDATA[Differential immunohistochemical expression of type I collagen and matrix metalloproteinase 2 among major salivary glands of young and geriatric mice]]> Abstract Objective This study aimed to demonstrate the immunohistochemical changes associated with MMP-2 and type 1 collagen separately for the first time in the major salivary glands (the parotid, submaxillary, and sublingual glands) that occur with aging in mice. Material and Methods Fourteen Balb/c white mice (50-80 g) were used in this study. The animals were divided into two equal groups. Group I consisted of young animals (2-month-old) (n=7) and Group II consisted of older animals (18-month-old) (n=7). After routine histological follow-ups, Hematoxylin-eosin (H&amp;E), Masson’s Trichrome staining and immunohistochemical staining was performed for type I collagen and MMP-2. Results We observed that there were age-related decreases in the number of acinar cells, increase in eosinophilic zymogen granules in cells, collagen accumulation in fibrotic areas and dilatation in interlobular ducts. Also, while type I collagen and MMP-2 immunoreactivity were moderate in the salivary glands of the young mice, they were high in the salivary glands of the old mice (p=0.001). In the H-score assessment, MMP-2 immunoreactivity was lower at a significant level in young mice than in old mice (p=0.001). Conclusions This study showed that anatomical, physiological and morphological abnormalities occur in all three major salivary glands as a natural consequence of aging. <![CDATA[Dental caries and bacterial load in saliva and dental biofilm of type 1 diabetics on continuous subcutaneous insulin infusion]]> Abstract Objectives Since most of the studies evaluates diabetics on multiple daily injections therapy and continuous subcutaneous insulin infusion may help gain better metabolic control and prevent complications, the objective of this study was to evaluate the prevalence of dental caries, the unstimulated salivary flow rate and the total bacteria load, Streptococcus spp. levels and Lactobacillus spp. levels in saliva and supragingival dental biofilm of type 1 diabetics on insulin pump. Material and Methods Sixty patients with type 1 diabetes on insulin pump and 60 nondiabetic individuals were included. The dental caries evaluation was performed using ICDAS and the oral hygiene was assessed according to Greene and Vermillion Simplified Oral Hygiene Index. Unstimulated saliva and supragingival dental biofilm were collected. Total bacteria, Streptococcus spp. and Lactobacillus spp. was quantified by qPCR. Results Patients with type 1 diabetes had a higher prevalence of dental caries and filled and missing teeth when compared with the control group. These patients were associated with more risk factors for the development of dental caries, namely a lower unstimulated salivary flow rate and a higher bacterial load in saliva and dental biofilm. Conclusion Some risk factors related to dental caries were associated with type 1 diabetics. An early diagnosis combined with the evaluation of the risk profile of the diabetic patient is imperative, allowing the dental caries to be analyzed through a perspective of prevention and the patient to be integrated into an individualized oral health program. <![CDATA[Standardization of a protocol for shotgun proteomic analysis of saliva]]> Abstract Saliva contains numerous proteins and peptides, each of them carries a number of biological functions that are very important in maintaining the oral cavity health and also yields information about both local and systemic diseases. Currently, proteomic analysis is the basis for large-scale identification of these proteins and discovery of new biomarkers for distinct diseases. Objective This study compared methodologies to extract salivary proteins for proteomic analysis. Material and Methods Saliva samples were collected from 10 healthy volunteers. In the first test, the necessity for using an albumin and IgG depletion column was evaluated, employing pooled samples from the 10 volunteers. In the second test, the analysis of the pooled samples was compared with individual analysis of one sample. Salivary proteins were extracted and processed for analysis by LC-ESI-MS/MS. Results In the first test, we identified only 35 proteins using the albumin and IgG depletion column, while we identified 248 proteins without using the column. In the second test, the pooled sample identified 212 proteins, such as carbonic anhydrase 6, cystatin isoforms, histatins 1 and 3, lysozyme C, mucin 7, protein S100A8 and S100A9, and statherin, while individual analysis identified 239 proteins, among which are carbonic anhydrase 6, cystatin isoforms, histatin 1 and 3, lactotransferrin, lyzozyme C, mucin 7, protein S100A8 and S100A9, serotransferrin, and statherin. Conclusions The standardization of protocol for salivary proteomic analysis was satisfactory, since the identification detected typical salivary proteins, among others. The results indicate that using the column for depletion of albumin and IgG is not necessary and that performing individual analysis of saliva samples is possible. <![CDATA[High-concentration carbamide peroxide can reduce the sensitivity caused by in-office tooth bleaching: a single-blinded randomized controlled trial]]> Abstract Objectives A single-blinded, randomized, parallel clinical trial evaluated the use of 37% carbamide peroxide (CP) on bleaching effectiveness and tooth sensitivity reported by patients undergoing in-office tooth bleaching, in comparison with the results of using 35% hydrogen peroxide. Material and Methods Forty patients were allocated to receive two sessions of in-office tooth bleaching using either 35% hydrogen peroxide (HP) or 37% CP. Each patient’s sensitivity level was evaluated during and up to 24 h after bleaching. The effectiveness of the bleaching procedures was evaluated with a spectrophotometer one week after each session and 30 days after the last session. The impact of tooth bleaching on the patients’ perceptions regarding smile changes, in addition to the bleaching procedures and their results, were also recorded. Absolute and relative sensitivity risks were calculated. Data on sensitivity level were analyzed using the Mann-Whitney or T-test, and data from the color evaluation were subjected to 2-way repeated measures ANOVA. Results The use of CP reduced the risk and level of tooth sensitivity to values close to zero, whereas the difference between the bleaching agents disappeared after 24 h. An increased bleaching effect was observed for HP, mainly due to an improved reduction of redness and yellowness. Participants perceived improved tooth bleaching for HP and reduced sensitivity for CP, but no differences regarding the comfort of the techniques were noted. Conclusions In our study, 37% CP resulted in reduced tooth sensitivity but decreased the tooth bleaching effectiveness. However, both bleaching agents resulted in high levels of patient satisfaction. <![CDATA[In-office tooth bleaching with 38% hydrogen peroxide promotes moderate/severe pulp inflammation and production of <em>ll-1β, TNF-β, GPX, FGF-2</em> and osteocalcin in rats]]> Abstract Objectives: To study the intensity of inflammatory infiltrate and production of interleukin-1β (ll-1β), tumor necrosis factor-β (TNF-β), fibroblast growth factor-2 (FGF-2), glutathione peroxidase (GPX), and osteocalcin in response to in-office tooth bleaching in rats. Material and Methods: Twenty male Wistar rats were randomized into four groups (n=5) according to the received treatment (tooth bleaching or no treatment - control) and the period of euthanasia after treatment (24 h or 10 days). We performed tooth bleaching using a 38% hydrogen peroxide gel on maxillary and mandibular incisors. After euthanasia, incisors (20 per group) were processed for histological analysis, immunohistochemistry staining of ll-1β, TNF-β, FGF-2 and GPX and osteocalcin by immunofluorescence. We analyzed data using the Mann-Whitney and Kruskal-Wallis/Dunn tests (p&lt;0.05). Results: The bleached groups presented statistically significant differences regarding the pulp inflammation stage compared with the control groups. Bleached teeth showed moderate/severe inflammatory infiltrate and control groups presented absent inflammatory cells or a negligible number of mononuclear cells (p&lt;0.001) at two times (24 h and 10 days). There was strong staining for ll-1β, TNF-β, and GPX in bleached groups at 24 h and strong staining for ll-1β, TNF-β, GPX and FGF-2 at 10 days. After 10 days of tooth bleaching, the bleached group showed a statistically superior amount of osteocalcin than the other groups (p&lt;0.01). Conclusions: Tooth bleaching with 38% hydrogen peroxide causes severe pulp inflammation, but characteristics of tissue repair after 10 days. <![CDATA[Alterations in the stomatognathic system due to amyotrophic lateral sclerosis]]> Abstract Objectives: To compare the molar bite force, electromyographic activity, chewing efficiency and thickness of the masseter and temporalis muscles in individuals with amyotrophic lateral sclerosis (ALS) and healthy individuals. Material and Methods: Thirty individuals enrolled in the study were divided into the study group (with ALS, n=15) and control group (healthy individuals, n=15). Data regarding molar bite force (right and left), electromyographic activity (mandibular rest, right and left laterality, protrusion, and maximum voluntary contraction), chewing efficiency (habitual and non-habitual), and masticatory muscle thickness (rest and maximum voluntary contraction) were tabulated and subjected to statistical analysis (Student’s t-test, p≤0.05). Results: Comparisons between the groups demonstrated a statistically significant increase in the electromyographic activity of the right masseter (p=0.03) and left masseter (p=0.03) muscles during mandibular rest; left masseter (p=0.00), right temporalis (p=0.00), and left temporalis (p=0.03) muscles during protrusion; and right masseter (p=0.00), left masseter (p=0.00), and left temporalis (p=0.00) muscles during left laterality, in individuals with ALS as compared with healthy individuals. A statistically significant decrease was observed in the habitual chewing efficiency of the right masseter (p=0.00) and right temporalis (p=0.04) muscles in individuals with ALS. No statistically significant difference between the groups was found the masticatory muscle thickness and maximal molar bite force. Conclusions: ALS may lead to modifications in the activities of the stomatognathic system, including muscular hyperactivity and reduction in chewing efficiency; however, no change has been observed in the masticatory muscle thickness and molar bite force. <![CDATA[Pro-inflammatory and anti-inflammatory cytokine expression in post-treatment apical periodontitis]]> Abstract Objective: This study evaluated the expression of pro-inflammatory (IL-1β, IL-6, IFN-γ and TNF-α) and anti-inflammatory (IL-4 and TGF-β) cytokines in apical periodontitis lesions. Correlations between these cytokines and clinical and cone-beam computed tomographic (CBCT) data were also assessed. Material and Methods: Apical periodontitis lesions’ data were obtained from 27 patients subjected to periradicular surgery. Specimens were processed for histopathologic and immunohistochemical analysis. Sections were evaluated according to the amount of positive staining for each antibody. Expression levels of the target mediators were compared with clinical and CBCT data. Results: Twenty lesions were diagnosed as granuloma and 7 as cyst. In granulomas, IL-4 expression was significantly higher than IL-6 (p=0.001) and TNF-α (p=0.001). There was a significant relationship between high levels of TNF-α and lesions &lt;5 mm (p=0.017). In cysts, IL-6 expression was significant lower than IL-4 (p=0.001) and IFN-γ (p=0.004). There was a significant relationship between high levels of TGF-β and endodontic treatment performed ≤4 years before (p=0.045). In general, IL-4 was the most expressed mediator in both cysts and granulomas. Conclusions: There was a balance between the expression of pro-inflammatory and anti-inflammatory cytokines associated with the chronic periradicular inflammatory process. TNF-α and TGF-β were related to some clinical and CBCT data. <![CDATA[Caries lesion remineralization with fluoride toothpastes and chlorhexidine - effects of application timing and toothpaste surfactant]]> Abstract Habitual toothbrushing with fluoridated toothpaste followed by rinsing with antibacterial mouthwashes is a method to maintain good oral hygiene and to diminish the occurrence and severity of dental caries and periodontal disease. However, our understanding of how antimicrobial agents in mouthwashes affect fluoride-mediated caries lesion remineralization is still poor. Objective: The objectives of this in vitro study were a) to determine the effects of the waiting period of chlorhexidine (CHX) rinsing after fluoride toothpaste use and b) to further determine the effect of the type of toothpaste surfactant [sodium dodecyl sulfate (SDS) or cocamidopropyl betaine (CAPB)] on caries lesion remineralization associated with CHX rinsing. Material and Methods: Caries lesions were formed in bovine enamel specimens and assigned to 10 treatment groups (n=18) based on Vickers surface microhardness (VHN). Lesions were then pH-cycled for 10 days with daily regimen comprised of twice daily toothpaste slurry treatments (1150 ppm fluoride, with SDS or CAPB), followed by CHX solution treatments [0, 15, 30 or 60 minutes following slurry treatment or no CHX treatment (negative control)]. VHN was measured again and the extent of lesion remineralization calculated (∆VHN). Results: ∆VHN with SDS-toothpaste was significantly lower than with CAPB-toothpaste, indicating more remineralization for the CAPB-toothpaste. ∆VHN with 0-minute waiting time was significantly lower than with 30-minute waiting time and with negative control. Conclusions: The absence of CHX as an adjunct to fluoride toothpastes led to greater remineralization of enamel lesions compared with the immediate use of CHX treatment for both SDS- and CAPB-toothpastes. CAPB-toothpastes indicated significantly greater remineralization than SDS-toothpastes, and can be suggested for patients at high risk of caries. A 30-minute waiting time for CHX treatment is recommended after brushing. <![CDATA[Oral implant osseointegration model in C57Bl/6 mice: microtomographic, histological, histomorphometric and molecular characterization]]> Abstract Despite the successful clinical application of titanium (Ti) as a biomaterial, the exact cellular and molecular mechanisms responsible for Ti osseointegration remains unclear, especially because of the limited methodological tools available in this field. Objective: In this study, we present a microscopic and molecular characterization of an oral implant osseointegration model using C57Bl/6 mice. Material and Methods: Forty-eight male wild-type mice received a Ti implant on the edentulous alveolar crest and the peri-implant sites were evaluated through microscopic (μCT, histological and birefringence) and molecular (RealTimePCRarray) analysis in different points in time after surgery (3, 7, 14 and 21 days). Results: The early stages of osseointegration were marked by an increased expression of growth factors and MSC markers. Subsequently, a provisional granulation tissue was formed, with high expression of VEGFb and earlier osteogenic markers (BMPs, ALP and Runx2). The immune/inflammatory phase was evidenced by an increased density of inflammatory cells, and high expression of cytokines (TNF, IL6, IL1) chemokines (CXCL3, CCL2, CCL5 and CXC3CL1) and chemokine receptors (CCR2 and CCR5). Also, iNOS expression remained low, while ARG1 was upregulated, indicating predominance of a M2-type response. At later points in time, the bone matrix density and volume were increased, in agreement with a high expression of Col1a1 and Col21a2. The remodelling process was marked by peaks of MMPs, RANKL and OPG expression at 14 days, and an increased density of osteoclasts. At 21 days, intimate Ti/bone contact was observed, with expression of final osteoblast differentiation markers (PHEX, SOST), as well as red spectrum collagen fibers. Conclusions: This study demonstrated a unique molecular view of oral osseointegration kinetics in C57Bl/6 mice, evidencing potential elements responsible for orchestrating cell migration, proliferation, ECM deposition and maturation, angiogenesis, bone formation and remodeling at the bone-implant interface in parallel with a novel microscopic analysis. <![CDATA[Efficacy of relacin combined with sodium hypochlorite against <em>Enterococcus faecalis</em> biofilms]]> Abstract Objective Relacin is a synthetic molecule that targets RelA, an essential protein in a conserved bacterial stress response system. It was shown to inhibit bacterial growth. The aims of this study were to evaluate the antimicrobial effect of relacin combined with sodium hypochlorite (NaOCl) on Enterococcus faecalis biofilms and to evaluate the cytotoxicity of relacin. Material and Methods 48-h E. faecalis OG1RF biofilms were treated by various concentrations of relacin in order to determine its inhibitory concentration. Then, the 48-h biofilms were treated either with 1-min NaOCl (0.01%, 0.05%) alone, or in combination of relacin. As a means of comparison, the biofilms of ΔrelA were also treated by 1-min NaOCl (0.01%, 0.05%, 0.25%). The treatment efficacy was determined by agar plate count assays. The cytotoxicity of relacin was examined on human gingival epithelial cells Ca9-22 and murine fibroblasts NIH-3T3 by a methyl thiazolyltetrazolium (MTT) assay and a lactate dehydrogenase assay. Statistical analysis was performed by one-way or two-way analysis of variance (ANOVA) with Bonferroni’s post-hoc test and an independent Student’s t-test. A significance level of p&lt;0.05 was used. Results Relacin inhibited the growth of OG1RF biofilms partially at 8 mM and fully at 14 mM. The relacin (14 mM) and NaOCl combined treatment resulted in significantly higher treatment efficacy than NaOCl treatment alone. At 0.05% NaOCl, the combined treatment resulted in 5.65 (±0.19) log reduction in biofilm viability. The ΔrelA biofilms were more susceptible to NaOCl treatment than the wild type biofilms at 0.25% NaOCl. Relacin at 14 mM was not toxic to host epithelial cells and fibroblasts. Conclusions The combination of relacin with a low concentration of NaOCl was effective and not cytotoxic. <![CDATA[Alveolar bone healing in rats: micro-CT, immunohistochemical and molecular analysis]]> Abstract Alveolar bone healing after upper incisor extraction in rats is a classical model of preclinical studies. The underlying morphometric, cellular and molecular mechanism, however, remains imprecise in a unique study. Objectives The aim of this study was therefore to characterize the alveolar bone healing after upper incisor extraction in rats by micro computed tomographic (Micro-CT), immunohistochemical and real-time polymerase chain reaction (RT-PCR) analysis. Material and Methods Thirty animals (Rattus norvegicus, Albinus Wistar) were divided into three groups after upper incisors extraction at 7, 14, and 28 days. Micro-CT was evaluated based on the morphometric parameters. Subsequently, the histological analyses and immunostaining of osteoprotegerin (OPG), receptor activator of nuclear kappa B ligand (RANKL) and tartrate resistant acid phosphate (TRAP) was performed. In addition, RT-PCR analyses of OPG, RANKL, the runt-related transcription factor 2 (RUNX2), osteocalcin (OC), osteopontin (OPN), osterix (OST) and receptor activator of nuclear kappa B (RANK) were performed to determine the expression of these proteins in the alveolar bone healing. Results Micro-CT: The morphometric parameters of bone volume and trabecular thickness progressively increased over time. Consequently, a gradual decrease in trabecular separation, trabecular space and total bone porosity was observed. Immunohistochemical: There were no differences statistically significant between the positive labeling for OPG, RANKL and TRAP in the different periods. RT-PCR: At 28 days, there was a significant increase in OPG expression, while RANKL expression and the RANKL/OPG ratio both decreased over time. Conclusion Micro-CT showed the newly formed bone had favorable morphometric characteristics of quality and quantity. Beyond the RUNX2, OC, OPN, OST, and RANK proteins expressed in the alveolar bone healing, OPG and RANKL activity showed to be essential for activation of basic multicellular units during the alveolar bone healing. <![CDATA[Changes in bacterial number at different sites of oral cavity during perioperative oral care management in gastrointestinal cancer patients: preliminary study]]> Abstract Objective The objective of this study was to clarify differences in bacterial accumulation between gastrointestinal cancer patients who underwent severely invasive surgery and those who underwent minimally invasive surgery. Material and Methods We performed a preliminary investigation of gastrointestinal cancer patients who were treated at the Department of Surgery, Takarazuka Municipal Hospital, from 2015 to 2017 (n=71; 42 laparoscopic surgery, 29 open surgery) to determine changes in bacterial numbers at different sites of the oral cavity (tongue dorsum, gingiva of upper anterior teeth, palatoglossal arch), as well as mouth dryness and tongue coating indices. Specifically, patients received professional tooth cleaning (PTC), scaling, tongue cleaning, and self-care instruction regarding tooth brushing from a dental hygienist a day before the operation. Professional oral health care was also performed by a dental hygienist two and seven days after surgery. Oral bacteria numbers were determined using a bacterial counter with a dielectrophoretic impedance measurement method. Results The number of bacteria at all three examined sites were significantly higher in the open surgery group when compared to the laparoscopic surgery group on the second postoperative day. Relevantly, bacterial count in samples from the gingiva of the upper anterior teeth remained greater seven days after the operation in patients who underwent open surgery. Furthermore, the dry mouth index level was higher in the open surgery group when compared to the laparoscopic surgery group on postoperative days 2 and 7. Conclusions Even with regular oral health care, bacterial numbers remained high in the upper incisor tooth gingiva in gastrointestinal cancer patients who received open surgery. Additional procedures are likely needed to effectively reduce the number of bacteria in the gingival area associated with the upper anterior teeth. <![CDATA[Minimization of polymerization shrinkage effects on composite resins by the control of irradiance during the photoactivation process]]> Abstract High levels of shrinkage stress caused by volumetric variations during the activation process are one of the main problems in the practical application of composite resins. Objective The aim of this study is to reduce the shrinkage stress and minimize the effects caused by composite resin volumetric variation due to the photopolymerization. In this way, this work proposes a systematic study to determine the optimal dimming function to be applied to light curing processes. Material and Methods The study was performed by applying mathematical techniques to the optimization of nonlinear objective functions. The effectiveness of the dimming function was evaluated by monitoring the polymerization shrinkage stress during the curing process of five brands/models of composites. This monitoring was performed on a universal testing machine using two steel bases coupled in the arms of the machine where the resin was inserted and polymerized. The quality of the composites cured by the proposed method was analyzed and compared with the conventional photoactivation method by experiments to determine their degree of conversion (DC). Absorbance measurements were performed using Fourier-transform infrared spectroscopy (FT-IR). A T-test was performed on DC results to compare the photoactivation techniques. We also used scanning electron microscopy (SEM) to analyze in-vitro the adhesion interface of the resin in human teeth. Results Our results showed that the use of the optimal dimming function, named as exponential, resulted in the significant reduction of the shrinkage stress (~36.88% ±6.56 when compared with the conventional method) without affecting the DC (t=0.86, p-value=0.44). The SEM analyses show that the proposed process can minimize or even eliminate adhesion failures between the tooth and the resin in dental restorations. Conclusion The results from this study can promote the improvement of the composite resin light curing process by the minimization of polymerization shrinkage effects, given an operational standardization of the photoactivation process. <![CDATA[Maxillomandibular giant osteosclerotic lesions]]> Abstract Giant Osteosclerotic Lesions (GOLs) are a group of rarely reported intraosseous lesions. Their precise diagnosis is important since they can be confused with malignant neoplasms. Objective This retrospective study aimed to record and analyze the clinical and radiographic Giant Osteosclerotic Lesions (GOLs) detected in the maxillomandibular area of patients attending to our institution. Materials and Methods: Informed consent from the patients was obtained and those cases of 2.5 cm or larger lesions with radiopaque or mixed (radiolucid-radiopaque) appearance located in the maxillofacial bones were selected. Assessed parameters were: age, gender, radiographic aspect, shape, borders, size, location and relations to roots. Lesions were classified as radicular, apical, interradicular, interradicular-apical, radicular-apical or located in a previous teeth extraction area. Additionally, several osseous and dental developmental alterations (DDAs) were assessed. Results Seventeen radiopacities in 14 patients were found and were located almost exclusively in mandible and were two types: idiopathic osteosclerosis and condensing osteitis. GOLs were more frequent in females, and in the anterior and premolar zones. 94.2% of GOLs were qualified as idiopathic osteosclerosis and one case was condensing osteitis. All studied cases showed different osseous and dental developmental alterations (DDAs). The most common were: Microdontia, hypodontia, pulp stones, macrodontia and variations in the mental foramina. Conclusions GOLs must be differentiated from other radiopaque benign and malignant tumors. Condensing osteitis, was considered an anomalous osseous response induced by a chronic low-grade inflammatory stimulus. For development of idiopathic osteosclerosis, two possible mechanisms could be related. The first is modification of the normal turnover with excessive osseous deposition. The second mechanism will prevent the normal bone resorption, arresting the osseous breakdown process. <![CDATA[Long-term microwaving of denture base materials: effects on dimensional, color and translucency stability]]> Abstract While the combined effect of microwave irradiation with cleansing solutions on denture base materials has been investigated, the effects of only using microwave irradiation and, more importantly, in a long-term basis, was not studied yet. Objective The purpose of this study was to evaluate the effect of a long-term repeated microwaving on the dimensional, color and translucency stability of acrylic and polyamide denture base materials. Material and Methods Thirty two specimens (32 mm x 10 mm x 2.5 mm) from polyamide (Valplast) and PMMA (Vertex Rapid Simplified) denture base materials were made. Eight specimens from each material were immersed in distilled water (control) and 8 were subjected to microwave exposure at 450 W for 3 minutes for a period simulating 224 days of daily disinfection. Linear dimension, color change (ΔE*) and translucency parameter (TP) were measured at baseline and after certain intervals up to 224 cycles of immersion, using a digital calliper and a portable colorimeter. The results were analysed using two-way repeated measures ANOVA to estimate possible differences among predetermined cycles and material type. Regression analysis was also performed to estimate the trend of changes with time. Statistical evaluations performed at a significance level of 5%. Results Data analysis showed significant changes in length at baseline with an increasing number of cycles (p&lt;0.05) and a significant interaction of cycle-material (p&lt;0.001). The ΔΕ* parameter was significantly higher with a higher number of cycles (p&lt;0.001), but it did not vary between materials (p&gt;0.05). TP decreased similarly in both materials following microwave action but in a significantly higher level for Valplast (p&lt;0.001). Conclusions The results indicated that long-term repeated microwaving affects linear dimensional, color and translucency changes of both materials. Differences between PMMA and polyamide material were noted only in dimension and translucency changes. <![CDATA[Myofascial trigger points in patients with temporomandibular joint disc displacement with reduction: a cross-sectional study]]> Abstract Objective The objective of this retrospective study was to evaluate the impact of myofascial trigger points (MTrPs) in patients with articular disc displacement with reduction (DDWR) and to identify which clinical variables are associated with the concomitant presence of DDWR and MTrPs. Material and Methods 130 patients were selected that sought treatment due to joint pain, with ages ≥18 years, of both genders, with DDWR confirmed by magnetic resonance imaging. The sample was divided into two groups: Group 1, patients with DDWR and MTrPs (N=101); and Group 2, patients with DDWR and no MTrPs (N=29). Information on gender, age, pain duration, pain scores, and maximal interincisal distance (MID) were collected. The logistic regression model was used and the odds ratios (OR) was calculated (p&lt;0.05). Results Group 1 presented statistically significant higher mean pain scores (p=0.007), and smaller MID (p=0.0268) than Group 2. OR were significant for the pain scores (1.429), MID (0.937) and gender (women) (2.810). Conclusions Patients with DDWR and MTrPs had increased pain scores and a MID decrease compared to patients with DDWR and no MTrPs. The variables pain scores, MID, and gender (women) showed a significant association with the concomitant presence of DDWR and MTrPs. <![CDATA[Daily melatonin administration improves osseointegration in pinealectomized rats]]> Abstract The hypothesis of this study was that the peri-implant bone healing of the group of pinealectomized rats would differ from the control group. The samples were subjected to immunohistochemical, microtomographic (total porosity and connectivity density), and fluorochrome (mineralized surface) analyses. Objectives The goal of this study was to investigate the cellular changes and bone remodeling dynamics along the bone/implant interface in pinealectomized rats. Material and Methods The total of 18 adult male rats (Rattus norvegicus albinus, Wistar) was divided into three groups (n=6): control (CO), pinealectomized without melatonin (PNX) and pinealectomized with melatonin (PNXm). All animals were submitted to the first surgery (pinealectomy), except the CO group. Thirty days after the pinealectomy without melatonin, the second surgery was conducted, in which all animals received an implant in each tibia (36 titanium implants with surface treatment were installed – Implalife® São Paulo, SP, Brazil). By gavage, the rats of the PNX group received the vehicle solution, and the procedure. Results Immunohistochemical analysis for runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteopontin (OP) and osteocalcin (OC) showed that the bone repair process in the PNXm group was similar to that of the CO group, whereas the PNX group showed a delay. The microtomographic parameters of total porosity [Po(tot)] and bone surface (BS) showed no statistically significant differences, whereas for the connective density (Conn.Dn) a statistical difference was found between the CO and PNXm groups. Fluorochrome analysis of the active mineralized surface showed statistically significant difference between the CO and PNX and between the CO and PNXm groups. Conclusion The absence of the pineal gland impaired the bone repair process during osseointegration, however the daily melatonin replacement was able to restore this response. <![CDATA[Immunohistochemical and mRNA expression of RANK, RANKL, OPG, TLR2 and MyD88 during apical periodontitis progression in mice]]> Abstract Objective To evaluate and correlate, in the same research, the mRNA expression and the staining of RANK, RANKL, OPG, TLR2 and MyD88 by immunohistochemistry in the apical periodontitis (AP) progression in mice. Material and Methods AP was induced in the lower first molars of thirty-five C57BL/6 mice. They were assigned to four groups according to their euthanasia periods (G0, G7, G21 and G42). The jaws were removed and subjected to histotechnical processing, immunohistochemistry and real-time reverse transcription-PCR (qRT-PCR). Data were analyzed with parametric and nonparametric tests (α=0.05). Results An increase of positive immunoreactivity for RANK, RANKL, OPG, TLR2 and MyD88 was observed over time (p&lt;0.05). The RANKL expression was different between the groups G0 and G42, G21 and G42 (p=0.006), with G42 presenting the higher expression in both comparations. The OPG expression was statistically different between the groups G0 and G7, G7 and G21 and G7 and G42 (p&lt;0.001), with G7 presenting higher expression in all the time points. The TLR2 expression was different between the groups G0 and G42 (p=0.03), with G42 showing the higher expression. The MyD88 expression presented a statistical significant difference between groups G7, G21 and G42 compared with G0 (p=0.01), with G0 presenting the smallest expression in all the comparisons. The Tnfrsf11/Tnfrsf11b (RANKL/OPG) ratio increased with the AP progression (p=0.002). A moderate positive correlation between MyD88 and RANKL (r=0.42; p=0.03) and between MyD88 and TLR2 (r=0.48; p&lt;0.0001) was observed. Conclusion The expression of the RANK, RANKL, OPG, MyD88 and TLR2 proteins as well as the ratio Tnfrsf11/Tnfrsf11b (RANKL/OPG) increased with AP progression. There was also a moderate positive correlation between the expression Myd88-Tnfrsf11 and Tlr2-Myd88, suggesting the relevance of Tlr2-Myd88 in bone loss due to bacterial infection. <![CDATA[Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin]]> Abstract Objectives Using two groups of mini-implants (successful and failed) the objectives of this in vivo study were: to evaluate the microbial contamination by the checkerboard DNA-DNA hybridization technique and to quantify the bacterial endotoxin by the limulus amebocyte lysate assay. Material and Methods The 15 successful and 10 failed mini-implants (1.6 mm diameter × 7.0 or 9.0 mm long), placed in the maxilla and/or mandible, were obtained from 15 patients undergoing orthodontic treatment. Data were analyzed statistically by the Wilcoxon rank-sum test using the SAS software (a=0.05). Results All 40 microbial species were detected in both groups of mini-implants, with different frequencies. No differences were observed between the groups with respect to microbial complexes (blue, purple, yellow, green, orange, red and other species) and endotoxin quantification (p&gt;0.05). Conclusion Neither microbial contamination nor endotoxin quantification was determinant for the early loss of stability of the mini-implants. <![CDATA[Effects of platelet-rich plasma on human gingival fibroblast proliferation and migration <em>in vitro</em>]]> Abstract Objective This study evaluated the influence of platelet-rich plasma (PRP) on the behaviour of human gingival fibroblasts (hGFs), including fibroblast proliferation, migration and colony formation. Methods PRP was obtained from the human peripheral blood of a healthy volunteer and then was diluted into platelet concentrations of 1%, 2% and 5%. The proliferation of hGFs was determined by two methods: (1) Cell-number counting with a haemocytometer method at days 1, 3, 5 and 7; (2) Colony-forming unit-fibroblast (CFU-F) assay at 2 weeks. The migration of hGFs was evaluated with scratch assay, then recorded digital images were analysed by Image-Analysis J 1.51j8 software to compare the remaining artificial wound areas between PRP groups at 0, 24 and 48 hours. Results All hGFs that were cultivated in media with 1%, 2% and 5% PRP showed their ability to proliferate and migrate. Cell numbers incubated with 1% PRP increased significantly during the first three days and peaked at day 5, tending to be similar to their proliferation in complete medium. With concentrations of 2% and 5% PRP, hGFs outgrew and peaked at day 3, which was faster than with those in medium with 1% PRP. Especially, hGFs in the group 5% PRP proliferated with higher cell numbers than those in the other remaining groups at day 3. The hGF colony number that was formed in the group 5% PRP was significantly higher than those in the groups 1% and 2% PRP. Scratch assay showed hGFs in the groups 2% and 5% PRP almost filled the artificial wound and migrated more effectively than in the group 1% PRP at 24 hours, which was significant. Conclusion In this study, perhaps the medium with 5% PRP is the dominant option, promoting the abilities of hGFs to heal wounds, because of its fast and effective impact on cell proliferation, colony formation and migration. <![CDATA[Effects of hyperbaric oxygen treatment on implant osseointegration in experimental diabetes mellitus]]> Abstract Objective To evaluate whether hyperbaric oxygen (HBO) treatment has a favorable effect on implant osseointegration in diabetic rabbits. Material and Methods An experimental diabetes model was induced in 32 New Zealand rabbits through IV injection of alloxan. After the state of diabetes had been confirmed, one dental implant was placed in the metaphysical region of each animal’s tibia. After the implants’ placements, the animals were divided into two groups. Half of the animals underwent HBO treatment, while the other group did not receive HBO treatment and served as the control group. The animals were euthanized at the 4th and 8th weeks. The osseointegration of the implants were compared by histomorphometry and resonance frequency analysis (RFA). Results The Bone Implant Contact (BIC) values were significantly higher in the HBO group than in the control group at the 4th week. There was no difference in the BIC values between the groups at the 8th week. There was no significant difference in the RFA scores between the groups both at the 4th and 8th weeks after the operation. Conclusion Histomorphometry findings suggest that HBO has positive effect on implant osseointegration in the early healing period in diabetic rabbits. However, implant stability is not affected by HBO treatment. <![CDATA[Communicative performance and vocabulary domain in preschool preterm infants]]> Abstract Objective The objective of this study was to evaluate and compare the performance of children in preschool age who were born premature and term, without neurological injury, regarding receptive and expressive language skills, and to reflect on the importance of these skills for performance in preschool. Materials and Methods Two groups named Preterm Group and Comparison Group, each composed by 40 children, as well as 80 legal representatives (mothers) and 80 teachers of the participants. To pair the groups, we considered chronological age (months), sex, educational level, type of school (public or private) and socioeconomic status. To assess the groups we used structured and semi-structured Observation of Communicative Behavior and applied the ABFW Child Language Test - Part B-Vocabulary and the Peabody Picture Vocabulary Test. To assess the legal representatives we applied an anamnesis questionnaire and the MacArthur Communicative Development Inventory. The assessment of the teachers consisted of the MacArthur Communicative Development Inventory and a Student Assessment Protocol developed by the authors. Results For the observation of communicative behavior, the categories with the highest losses were: narrative, maintaining dialogic activities and attention difficulties. In the ABFW Child Language Test and Peabody Picture Vocabulary Test there were statistically significant differences. In the MacArthur Communicative Development Inventory there were statistically significant differences in expressive vocabulary, but no differences in receptive vocabulary, for both the mothers and the teachers. Conclusion Children born prematurely with low risk of neurological sequelae in preschool age may have greater difficulties in linguistic performance than their peers born to term. <![CDATA[Effects of diode laser application on inflammation and mpo in periodontal tissues in a rat model]]> Abstract Objective In this study, we aimed to histologically and immunologically evaluate the effect of diode laser treatment when applied adjunctive to scaling and root planing (SRP) in an experimental periodontitis model. Materials and methods We used Wistar-Albino rats (n=60) with average weight of 230 g. Experimental periodontitis was induced by ligature at the right and left first mandibular molar teeth in all rats. After 11 days, the ligature was removed and rats were divided into two groups. The control group (n=30) received only SRP treatment, while the laser group (n=30) received a diode laser (GaAlAs, 810 nm, 1 W, 10 J, 20 s) treatment adjunctive to SRP. Ten rats in each group were sacrificed after 7, 15, and 30 days. Histopathological examination was performed in the left mandible of rats. Myeloperoxidase (MPO) was evaluated by western blot in the gingival specimens from the right mandible. Results MPO levels in the laser group were statistically significantly lower compared with the control group (p≤0.05). There was no statistically significance at any time between MPO levels in the control group (p&gt;0.05). MPO levels in the laser group at the 7th day were statistically significantly higher compared to the 15th (p≤0.05) and the 30th day (p≤0.05). Inflammatory cell infiltration decreased over time in both groups and was statistically significantly lower in the laser group than in the control group at all times (p≤0.01). Conclusions Within the limits of this study, we suggest that diode laser application is an adjunctive treatment because it reduced inflammation and MPO when applied in addition to SRP. On the other hand, more studies are needed for the assessment of the effects of diode laser application to periodontal tissues. <![CDATA[Study of the chemical interaction between a high-viscosity glass ionomer cement and dentin]]> Abstract Objective To investigate the chemical interactions between a high-viscosity glass ionomer cement (GIC) (KetacTM Molar Easymix, 3M ESPE, Seefeld, Bavaria, Germany) and human dentin. It was also analyzed the dynamics of GIC setting mechanism based on the time intervals required for the GIC and the GIC mixed with dentin to achieve stability. Material and Methods Each constituent of GIC – powder (P) and liquid (L) – and powdered dentin (D), as well as the associations P+L, D+L, and P+L+D in the concentrations of 29%, 50%, 65%, 78%, 82%, and 92% of GIC were analyzed with Fourier transform infrared (FTIR) and Raman spectroscopy. Results New optical absorption bands and/or Raman bands, which were not present in P, L, or D, were observed in the associations. The concentrations of 29% and 50% of GIC showed higher interaction, revealing that the amount of dentin influences the formation of new optical absorption or scattering bands. FTIR bands showed that the setting time to achieve bond stability was longer for the high-viscosity GIC (38±7 min) than for the sample with 29% of GIC (28±4 min). Conclusions The analysis revealed the formation of new compounds or molecular rearrangements resulting from the chemical interactions between GIC and dentin. Moreover, this study provides an effective method to evaluate the dynamics of the setting mechanism of GICs. <![CDATA[Tomographic late evaluation of xenogeneic bone grafts in sockets of impacted third molars]]> Abstract It is necessary to preserve height and thickness of the alveolar bone to facilitate rehabilitation with osteointegratable implants or simply to maintain bone integrity after extraction. Biomaterials associated with resorbable or non-resorbable membranes, when placed in the region of the socket, may contribute to avoid this unwanted reabsorption. Objective The objective of this study was to evaluate the distance of the crest of alveolar ridge to the cementoenamel junction (CEJ) of the lower second molars and the bone density of the third molar socket filled with Gen-Tech®, 5 years after an exodontia using cone beam computed tomography (CBCT) to visualize the central region of the sockets, without overlapping of the buccal and lingual cortical bones. Material and Methods A total of 12 individuals from an initial group of 39 patients submitted to extraction of the unruptured lower third molars and grafting of an association of inorganic bovine bone matrix, organic bovine bone matrix, collagen and bone morphogenetic proteins (BMP) (Gen-Tech®) on one side and the contralateral sockets filled only by clot, returned to control after 5 years, and were submitted to CBCT. The distance from the crest of alveolar bone to the CEJ and the bone density (BD) were measured using the i-CAT Vision Software. Results The results showed that the distance from the crest of alveolar bone to the CEJ in the control group was similar to that observed before the exodontia; in the experimental group, this distance was smaller. Considering the BD measurement, a significantly higher density was observed in the experimental group (p&lt;0.05). Conclusion Part of the biomaterial was not absorbed and allowed the stability of the evaluated parameters after 5 years, being able to be used as a bone substitute in the socket. <![CDATA[Relationship between phonological working memory, metacognitive skills and reading comprehension in children with learning disabilities]]> Abstract Reading requires the activation of several cognitive processes, some of which are basic, e.g. recognizing letters and words, whereas others are complex, such as working memory and ability to think about one's own learning strategies. One condition for fulfilling a complex cognitive task, such as understanding a text, is the ability to maintain and process information, which depends on working memory. Objective To analyze the ability of using metacognitive strategies for reading, the phonological working memory of school children with learning disabilities, and also determine if there is relation between these skills and reading comprehension. Method The sample consisted of 30 school-age children and teenagers of both genders, aged 8 to 12 years, who were enrolled in primary school. They were divided in two groups, experimental (EG) and control (CG). All children were subjected to evaluation of reading comprehension, phonological working memory, and use of metacognitive skills for reading. The results were compared between groups through the Mann-Whitney test, and correlation between variables was analyzed through Spearman correlation test. Result Statistical comparison between EG and CG showed statistically significant difference. Positive and effective correlation was observed between reading comprehension, phonological working memory and metacognitive tests. Conclusion children with learning disabilities presented deficits in phonological working memory and use of metacognitive strategies. The positive and effective correlation between the abilities analyzed suggests that failure in the phonological working memory and use of metacognitive strategies interfere with reading comprehension. <![CDATA[The association between periodontal conditions, inflammation, nutritional status and calcium-phosphate metabolism disorders in hemodialysis patients]]> Abstract Objectives To analyze the association between periodontal conditions and inflammation, nutritional status and calcium-phosphate metabolism disorders in hemodialysis (HD) patients. Material and Methods We analyzed 128 HD patients divided into two groups: dentate (n = 103) and edentulous (n=25). The following items were assessed: baseline characteristics, age at the start and duration of HD, biochemical data: C-reactive protein (CRP), serum albumin, calcium, phosphorus, alkaline phosphatase, parathormone. A single dentist performed a complete dental/periodontal examination, including parameters of oral hygiene and gingival bleeding. Results One person had healthy periodontium, 62.14% of the patients had gingivitis, and 36.9% had moderate or severe periodontitis. The age at HD onset had a positive impact on periodontal status and negatively correlated with the number of teeth. A positive correlation between age and CRP level and negative correlations between age and serum albumin and phosphorus were found. Pocket depth (PD) was negatively correlated with serum albumin. The number of teeth was negatively correlated with serum CRP. Conclusions High prevalence and severity of periodontal disease are observed in hemodialysis patients. There is a high probability that periodontal disease may be present at the early stages of chronic kidney disease (CKD) before the hemodialysis onset. <![CDATA[Effect of non-surgical periodontal therapy on the degree of gingival inflammation and stress markers related to pregnancy]]> Abstract Objectives The purpose of this study was to determine the impact of nonsurgical periodontal therapy considering the salivary stress-related hormone and cytokine levels in the gingival crevicular fluid (GCF) on pregnant and nonpregnant women. Material and Methods Thirty non-pregnant (control group) and 30 pregnant women (test group) that met the study inclusion criteria were chosen. Only participants with gingivitis were included. Clinical data and samples of GCF and saliva were collected at baseline and after periodontal therapy. The levels of interleukin-1 beta (Κ-1β) and IL-10, and concentration of salivary chromogranin A (CgA) hormone were analyzed by enzyme-linked immunosorbent assay (ELISA). The repeated measures analysis of variance was used for intragroup and intergroup analyses. Results A major decrease in the gingival inflammation was observed in both groups after periodontal therapy (p&lt;0.05). Periodontal treatment decreased the level of IL-1β in GCF (p&lt;0.05) in control group, but no statistical difference was determined for GCF IL-1β in the test group. However, after periodontal therapy, the CgA hormone concentration was reduced in both groups (p&lt;0.05). However, there was no difference in salivary CgA concentration, GCF IL-10 levels, and perceived stress scale (PSS)-10 between the groups (p&gt;0.05). Conclusions Within the limitations of this study, periodontal therapy significantly improved the periodontal status and stress level. In addition, the severity of the gingival inflammation during pregnancy was related to stress. However, further studies will be needed to substantiate these early findings. <![CDATA[Evaluation of physical-mechanical properties, antibacterial effect, and cytotoxicity of temporary restorative materials]]> Abstract The objective of this study was to compare selective physical-mechanical properties, antibacterial effects and cytotoxicity of seven temporary restorative materials (TRM): five resin-based materials [Bioplic (B), Fill Magic Tempo (FM), Fermit inlay (F), Luxatemp LC (L) and Revotek LC (R)], and zinc oxide-eugenol cement (IRM) and glass ionomer cement (GIC) as the controls. Material and methods The physical-mechanical properties were evaluated by determining microleakage (ML), ultimate tensile strength (UTS) and Shore D hardness (SDH). In addition, the polymerization rate (Pr-1), depth of cure (DC), water sorption and solubility (WS/SL) were evaluated. The antimicrobial effects of the materials were assessed by biofilm accumulation of Streptococcus mutans (BT) and the direct contact test (DCT) by exposure to Enterococcus faecalis for 1 and 24 h, and cytotoxicity by MTT assay. The data were analyzed by ANOVA or Kruskall-Wallis tests, and a complementary post-hoc method (p&lt;0.05). Results Group B, followed by FM and GIC had significantly lower percentages of microleakage in comparison with the other groups; Groups FM and L showed the highest WS, while Groups R and FM showed the significantly lowest SL values (p&lt;0.05). Group R showed the statistically highest UTS mean and the lowest DC mean among all groups. Group F showed the lowest S. mutans biofilm accumulation (p=0.023). Only the Group L showed continued effect against E. faecalis after 1 h and 24 h in DCT. The L showed statistically lower viability cell when compared to the other groups. Conclusions These findings suggest the antibacterial effect of the temporary materials Fill Magic and Bioplic against S. mutans, while Luxatemp showed in vitro inhibition of S. mutans biofilm accumulation and E. faecalis growth. Regarding the cell viability test, Luxatemp was the most cytotoxic and Fill Magic was shown to be the least cytotoxic. <![CDATA[Effect of cavity preparation design and ceramic type on the stress distribution, strain and fracture resistance of CAD/CAM onlays in molars]]> Abstract Objective This study aimed to evaluate the effect of the cavity preparation and ceramic type on the stress distribution, tooth strain, fracture resistance and fracture mode of human molar teeth restored with onlays. Material and Methods Forty-eight molars were divided into four groups (n=12) with assorted combinations of two study factors: BL- conventional onlay preparation with boxes made from leucite ceramic (IPS-Empress CAD, Ivoclar Vivadent); NBL- conservative onlay preparation without boxes made from leucite ceramic; BD- conventional onlay preparation with boxes made from lithium disilicate glass ceramic (IPS e.max CAD, Ivoclar Vivadent); NBL- conservative onlay preparation with boxes made from lithium disilicate glass ceramic cuspal deformation (µS) was measured at 100 N and at maximum fracture load using strain gauge. Fracture resistance (N) was measured using a compression test, and the fracture mode was recorded. Finite element analysis was used to evaluate the stress distribution by modified von Mises stress criteria. The tooth strain and fracture resistance data were analyzed using the Tukey test and two-way ANOVA, and the fracture mode was analyzed by the chi-square test (α=0.05). Results The leucite ceramic resulted in higher tooth deformation at 100 N and lower tooth deformation at the maximum fracture load than the lithium disilicate ceramic (P&lt;0.001). The lithium disilicate ceramic exhibited higher fracture resistance than the leucite ceramic (P&lt;0.001). The conservative onlay resulted in higher fracture strength for lithium disilicate ceramic. Finite element analysis results showed the conventional cavity preparation resulted in higher stress concentration in the ceramic restoration and remaining tooth than the conservative onlay preparation. The conservative onlays exhibited increased fracture resistance, reduced stress concentration and more favorable fracture modes. Conclusion Molars restored with lithium disilicate CAD-CAM ceramic onlays exhibited higher fracture resistance than molars restored with leucite CAD-CAM ceramic onlays. <![CDATA[Cyclic flexural fatigue resistance of NiTi Controlled Memory and Blue Technology instruments after torsional preloading]]> Abstract Objective The aim of this study was to evaluate the influence of torsional preloading on the cyclic flexural fatigue resistance of thermally treated NiTi instruments. Material and Methods Ten new instruments New Hyflex CM (HF 30.06; Coltene/Whaladent Inc.), Typhoon CM (TYP 30.06; Clinician's Choice Dental Products) and Vortex Blue (VB 30.06; Dentsply Tulsa Dental) were chosen, based on geometry and specific characteristics of the manufacturing process. The new instruments of each system were tested in a bench device to determine their fatigue resistance through mean value of number of cycles to failure (Nf) (Control Group – CG). Another group of 10 new HF, TYP and VB instruments were submitted to 20 cycles of torsional straining between 0° and 180° (Experimental Group – EG) and then submitted to fatigue until rupture under the same conditions of the CG. Tested instruments were examined by scanning electron microscopy (SEM). Data were analyzed using one-way analysis of variance and post hoc Tukey’s test (α=.05). Results Higher fatigue resistance was accomplished by HF instruments, followed by VB and TYP (p&lt;0.05). During the torsional preloading, the lowest mean torque value was observed for TYP instruments (p&lt;0.05). The torsional preload caused a significant reduction in the Nf values (p&lt;0.05) of about 20%, 39% and 45% for instruments HF, VB and TYP, respectively. Longitudinal cracks, generated during the torsional preloading, were present in VB files, but were not observed in the CM instruments (HF and TYP). Conclusions In conclusion, the flexural fatigue resistance of thermally treated instruments is diminished after cyclic torsional loading. <![CDATA[One-year prospective clinical study comparing patient satisfaction and masticatory performance of mandibular overdentures supported by one versus two implants]]> Abstract There is a lack of clinical evidence on mandibular overdentures (MOD) supported by a single implant. Objective: To compare patient satisfaction and masticatory performance in MOD supported by one versus two implants in a two-group parallel randomized clinical trial. Material and Methods: Twenty-one patients wearing new maxillary and mandibular complete dentures (CDs) were randomly divided to receive one (GI, n = 11) or two (GII, n = 10) implants in the mandibular arch. Four months after implant placement, o-ring abutments were installed in the implants, and matrix attachments were placed in the lower complete dentures. Patient satisfaction with their dentures and masticatory performance were compared at baseline, 3, 6, and 12 months after the procedure. Data on patient satisfaction were analyzed using the Friedman test and the Mann-Whitney U test. Data on masticatory performance were analyzed using one-way repeated measures analysis of variance (ANOVA) and Student's t test (α=0.05). Results: Both groups exhibited a significant increase in overall patient satisfaction in all periods evaluated (p&lt;0.05), except for GI after 12 months, which had values similar to baseline (p=0.74). Satisfaction levels of GI and GII were similar at baseline, 3 and 6 months, but GII showed higher satisfaction levels (p=0.01) than GI at 12 months. GI and GII exhibited a significant increase (p&lt;0.05) in masticatory performance for all periods relative to baseline. However, GII had higher masticatory performance with dentures than GI, regardless of the period (p&lt;0.05). Conclusion: MOD supported by two implants demonstrated better patient satisfaction in the follow-up at 12 months and better masticatory performance than MOD supported by one implant. <![CDATA[Volumetric reconstruction and determination of minimum crosssectional area of the pharynx in patients with cleft lip and palate: comparison between two different softwares]]> Abstract Objective: The aim of this study was to assess the accuracy of volumetric reconstruction of the pharynx by comparing the volume and minimum crosssectional area (mCSA) determined with open-source applications (ITK-Snap, ; SlicerCMF) and commercial software (Dolphin3D, 11.8, Dolphin Imaging &amp; Management Solutions, Chatsworth, CA, USA) previously validated in the literature. Material and Methods: The sample comprised of 35 cone-beam computed tomography (CBCT) scans of patients with unilateral cleft lip and palate, with mean age of 29±15. Three-dimensional volumetric models of the pharynx were reconstructed using semi-automatic segmentation using the applications ITK-Snap (G1) and Dolphin3D (G2). Volumes and minimum cross-sectional areas were determined. Inter- and intra-observer error were calculated using ICC test. Comparison between applications was calculated using the Wilcoxon test. Results: Volumes and minimum crosssectional area were statistically similar between applications. ITK-Snap showed higher pharynx volumes, but lower mCSA. Visual assessment showed that 62.86% matched the region of mCSA in Dolphin3D and SPHARM-PDM. Conclusion: Measurements of volume and mCSA are statistically similar between applications. Therefore, open-source applications may be a viable option to assess upper airway dimensions using CBCT exams. <![CDATA[IFN-γR2 is strongly expressed on endothelial cells of gingival tissues from patients with chronic periodontitis]]> Abstract Chronic periodontitis (CP) is characterized by gingival inflammation and bone destruction. It has been reported that interferon-gamma (IFN-γ) levels are high in CP patients; however, the IFN-γ receptor (IFN-γR) has not been studied in gingival tissue from these patients. Objective: To evaluate IFN-γ levels and IFN-γR expression in gingival tissue biopsies from chronic periodontitis patients compared with healthy subjects (HS). Material and Methods: Gingival tissues were obtained from all study subjects, CP (n = 18) and healthy subjects (HS) (n = 12). A tissue section of each study subject was embedded in paraffin blocks to determine the expression of IFN-γ R (IFN-γR1 and IFN-γR2) through immunohistochemistry. Another section of the tissue was homogenized and IFN-γ was measured by the ELISA technique. Results: No significant differences were found in the IFN-γR1 expression within the cell layers of the gingival tissue of the study groups. When analyzing the IFN-γR2 expression it was found that IFN-γR2 is strongly expressed in the endothelial cells of CP patients when compared to HS (p&lt;0.05). IFN-γ concentrations in the gingival tissue were significantly higher in CP patients than in HS. No significant correlation between IFN-γ levels and the expression of IFN-γR1 and IFN-γR2 was found. However, a positive correlation between IFN-γ levels and clinical parameters [probing depth (PD) and clinical attachment level (CAL)] was found. Conclusion: The study of IFN-γR expression in gingival tissue samples from patients with CP showed an increase only in the IFN-γR2 chain in endothelial cells when compared to HS. <![CDATA[Quorum sensing LuxS/autoinducer-2 inhibits <em>Enterococcus faecalis</em> biofilm formation ability]]> Abstract Objective: To investigate the relation between biofilm formation ability and quorum sensing gene LuxS/AI-2. Materials and Methods: Enterococcus faecalis (E. faecalis) standard strain ATCC 29212 was used in the study. Long flanking homology polymerase chain reaction method was used to build the LuxS gene knockout strain. Sequential culture turbidity measurement and CFU counting were used to assess the proliferation ability of E. faecalis after the depletion of LuxS. 96-well plate assay was used to quantify the biofilm formation ability; CLSM was used to observe the attached bacteria areas, while scanning electron microscopy (SEM) was performed to observe biofilm microstructure conditions. Results: LuxS gene knockout strains were successfully constructed and identified. The results showed that proliferation ability of E. faecalis was not affected by the depletion of the luxS gene, and the biofilm formation ability of ΔLuxS 29212 significantly decreased (P&lt;0.05). Conclusions: Collectively, our studies provide the LuxS gene's key role in controlling biofilm formation of E. faecalis, which presented a negative regulation, and furthermore, providing us a possible way to conquer the persistent apical periodontitis. <![CDATA[Effects of experimental bleaching agents on the mineral content of sound and demineralized enamels]]> Abstract High concentrations of hydrogen peroxide can cause adverse effects on composition and structure of teeth. However, the addition of calcium and fluoride in bleaching agents may reduce enamel demineralization. Objective: To evaluate chemical changes of sound and demineralized enamels submitted to high concentrations of hydrogen peroxide containing fluoride (F) or calcium (Ca). Material and Methods: Enamel blocks of bovine incisors with standard dimensions were obtained and half of them were submitted to pH-cycling to promote initial enamel caries lesions. Sound and demineralized enamel samples were divided into (n=10): (C) Control (no whitening treatment); (HP) 35% hydrogen peroxide; and two experimental groups: (HPF) 35% HP+0.2% F and (HPC) 35% HP+0.2% Ca. Experimental groups were submitted to two in-office bleaching sessions and agents were applied 3 times for 15 min to each session. The control group was kept in remineralizing solution at 37°C during the bleaching treatment. The surface mineral content of sound and demineralized enamels was determined through Fourier Transform Raman spectroscopy (FT-Raman), Energy dispersive Micro X-ray fluorescence spectroscopy (μ-EDXRF); and the subsurface, through cross-sectional microhardness (CSMH). In addition, polarized light microscopy (PLM) images of enamel subsurface were observed. Results: According to three-way (FT-Raman and μ-EDXRF analyses) or two-way analysis of variance (ANOVA) (CSMH) and Tukey test (α=5%), the calcium or fluoride added to high-concentrated bleaching agents increased phosphate and carbonate concentrations on sound and demineralized enamels (p&lt;0.05). However, HPC and HPF were unable to completely reverse the subsurface mineral loss promoted by bleaching on sound and demineralized enamels. The calcium/ phosphate (Ca/P) ratio of sound enamel decreased after HP treatment (p&lt;0.001). Conclusion: Even though experimental bleaching agents with Ca or F reduced mineral loss for both sound and demineralized enamel surfaces, these agents were unable to reverse the enamel subsurface demineralization. <![CDATA[Pulp analysis of teeth submitted to different types of forces: a histological study in rats]]> Abstract Objective: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces. Material and Methods: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations. The main observed alterations were related to hemodynamic pulp characteristics, such as presence of thrombosis, vascular congestion and hemorrhages. The hemodynamic alterations were statistically evaluated by Shapiro-Wilk normality test and analysis of variance by the Kruskall-Wallis test. Results: There was no significant differences observed between groups in the different types of applied forces and duration of ITM (vascular congestion, p=1.000; hemorrhage, p=0.305; thrombosis, p=1.000). Conclusions: Pulp tissue alterations resulting from ITM were limited to hemodynamic events, without progressing to irreversible degeneration, regardless of the type of force applied. <![CDATA[The role of potassium channels in the endothelial dysfunction induced by periodontitis]]> Abstract Objective: Periodontitis is associated with endothelial dysfunction, which is clinically characterized by a reduction in endothelium-dependent relaxation. However, we have previously shown that impairment in endothelium-dependent relaxation is transient. Therefore, we evaluated which mediators are involved in endothelium-dependent relaxation recovery. Material and methods: Rats were subjected to ligature-induced experimental periodontitis. Twenty-one days after the procedure, the animals were prepared for blood pressure recording, and the responses to acetylcholine or sodium nitroprusside were obtained before and 30 minutes after injection of a nitric oxide synthase inhibitor (L-NAME), cyclooxygenase inhibitor (Indomethacin, SC-550 and NS- 398), or calcium-dependent potassium channel blockers (apamin plus TRAM- 34). The maxilla and mandible were removed for bone loss analysis. Blood and gingivae were obtained for C-reactive protein (CRP) and myeloperoxidase (MPO) measurement, respectively. Results: Experimental periodontitis induces bone loss and an increase in the gingival MPO and plasmatic CRP. Periodontitis also reduced endothelium-dependent vasodilation, a hallmark of endothelial dysfunction, 14 days after the procedure. However, the response was restored at day 21. We found that endothelium-dependent vasodilation at day 21 in ligature animals was mediated, at least in part, by the activation of endothelial calcium-activated potassium channels. Conclusions: Periodontitis induces impairment in endothelial-dependent relaxation; this impairment recovers, even in the presence of periodontitis. The recovery is mediated by the activation of endothelial calcium-activated potassium channels in ligature animals. Although important for maintenance of vascular homeostasis, this effect could mask the lack of NO, which has other beneficial properties. <![CDATA[Clinical wear of approximal glass ionomer restorations protected with a nanofilled self-adhesive light-cured protective coating]]> Abstract High viscous glass ionomer cement (GIC) has gained popularity as a restorative material; however, high wear is pointed as one of the major drawbacks of this material. Protective surface coatings were developed to protect GIC from water contamination with the additional advantage of occluding any surface cracks or porosities commonly found in this material, possibly resulting in an increased wear resistance of the restorations. Objective: The objective of this study was to investigate the clinical wear of GIC approximal restorations in primary molars protected either with a nanofilled self-adhesive light-cured protective coating (NPC) or with petroleum jelly. Material and Methods: Approximal caries lesions in primary molars from 32 schoolchildren previously enrolled in another clinical trial were included in this investigation. GIC restorations were performed according to the Atraumatic Restorative Treatment approach and protected with either petroleum jelly or a NPC. Impressions of the restored hemiarch were done after 1 day and 6, 12, 24 and 36 months. The impressions were scanned in a 3-D appliance and the obtained images were superimposed using an appropriate computer software. Two-way ANOVA for repeated measures and Tukey's post-hoc test were used to analyze the wear of restorations (α=5%). Results: A significant difference was found between the two groups, with a wear protection offered by the application of a NPC. Conclusion: These results suggest that the application of a NPC has a protective effect on the clinical wear of approximal GIC restorations in primary teeth. <![CDATA[Clear cell odontogenic carcinoma of the mandible: a treatment strategy]]> Abstract Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor of the jaws, histologically characterized by the presence of agglomerates of cells with eosinophilic cytoplasm. The patient, a 62-year-old Caucasian woman, presented an intraosseous lesion in the mandibular symphysis. A clinical examination revealed a discrete volumetric increase with a hard consistency, palpable to extraoral and intraoral examinations. Imaging studies revealed an extensive radiolucent area, without defined limits, extending from the region of the right second premolar to the left canine. Incisional biopsy analysis indicated a diagnosis of CCOC. The treatment proposed was segmental resection of the mandible with a safety margin. After six months without recurrence, definitive mandibular reconstruction was performed using an iliac crest graft, followed by rehabilitation with implant-supported denture after five months. After three years of post-resection follow-up, the patient has shown no evidence of recurrence or metastasis. She continues to be under follow-up. To conclude, CCOC must be considered a malignant tumor with aggressive behavior. Previous studies have shown that resection with free margins is a treatment with a lower rate of recurrence. Nevertheless, long-term follow-up is necessary for such patients. <![CDATA[ERRATUM: Neurosensory analysis of tooth sensitivity during at-home dental bleaching: a randomized clinical trial]]> Abstract Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor of the jaws, histologically characterized by the presence of agglomerates of cells with eosinophilic cytoplasm. The patient, a 62-year-old Caucasian woman, presented an intraosseous lesion in the mandibular symphysis. A clinical examination revealed a discrete volumetric increase with a hard consistency, palpable to extraoral and intraoral examinations. Imaging studies revealed an extensive radiolucent area, without defined limits, extending from the region of the right second premolar to the left canine. Incisional biopsy analysis indicated a diagnosis of CCOC. The treatment proposed was segmental resection of the mandible with a safety margin. After six months without recurrence, definitive mandibular reconstruction was performed using an iliac crest graft, followed by rehabilitation with implant-supported denture after five months. After three years of post-resection follow-up, the patient has shown no evidence of recurrence or metastasis. She continues to be under follow-up. To conclude, CCOC must be considered a malignant tumor with aggressive behavior. Previous studies have shown that resection with free margins is a treatment with a lower rate of recurrence. Nevertheless, long-term follow-up is necessary for such patients.