Scielo RSS <![CDATA[Journal of Applied Oral Science]]> http://www.scielo.br/rss.php?pid=1678-775720120002&lang=en vol. 20 num. 2 lang. en <![CDATA[SciELO Logo]]> http://www.scielo.br/img/en/fbpelogp.gif http://www.scielo.br <![CDATA[<b>The 50<sup>th</sup> anniversary and the 25<sup>th</sup> Dental Congress of the Bauru School of Dentistry of the University of São Paulo</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200001&lng=en&nrm=iso&tlng=en <![CDATA[<b>Modulation of host cell signaling pathways as a therapeutic approach in periodontal disease</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200002&lng=en&nrm=iso&tlng=en Recently, new treatment approaches have been developed to target the host component of periodontal disease. This review aims at providing updated information on host-modulating therapies, focusing on treatment strategies for inhibiting signal transduction pathways involved in inflammation. Pharmacological inhibitors of MAPK, NFκB and JAK/STAT pathways are being developed to manage rheumatoid arthritis, periodontal disease and other inflammatory diseases. Through these agents, inflammatory mediators can be inhibited at cell signaling level, interfering on transcription factors activation and inflammatory gene expression. Although these drugs offer great potential to modulate host response, their main limitations are lack of specificity and developments of side effects. After overcoming these limitations, adjunctive host modulating drugs will provide new therapeutic strategies for periodontal treatment. <![CDATA[<b>Bacteriology of deep carious lesions underneath amalgam restorations with different pulp-capping materials - an <i>in vivo</i> analysis</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200003&lng=en&nrm=iso&tlng=en Microorganisms remaining in dentin following cavity preparation may induce pulp damage, requiring the use of pulp-capping agents with antimicrobial activity underneath permanent restorations. OBJECTIVE: The aims of this study were to analyze the bacteriological status of carious dentin and to assess the efficacy of different base underneath silver amalgam restorations. MATERIAL AND METHODS: This study was conducted on 50 patients aged 13 to 30 years. Sterile swabs were used to take samples after cavity preparation, which was assessed by microbiological culture to identify the microorganisms present. Following this, cavities were restored with silver amalgam, using one of the materials being investigated, as the base: calcium hydroxide (Group II), polyantibiotic paste (Group III), a novel light-cured fluoride-releasing hydroxyapatite-based liner (Group IV) and mineral trioxide aggregate - MTA (Group V). In Group I, the cavities were restored with silver amalgam, without any base. After 3 months, the amalgam was removed and samples taken again and analyzed for the microbial flora. RESULTS: Lactobacilli were the most commonly isolated microorganisms in the samples of carious dentin. Groups IV and V showed negative culture in the 3-month samples. There was no statistically significant difference between Groups I, II and III. There was no significant difference between Groups IV and V (p&gt;0.05). Both Groups IV and V showed significantly better results when compared to Groups I, II and III (p<0.05). CONCLUSIONS: The hydroxyapatite-based liner and MTA performed significantly better in terms of antibacterial activity than the other materials. <![CDATA[<b>Xylitol concentrations in artificial saliva after application of different xylitol dental varnishes</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200004&lng=en&nrm=iso&tlng=en OBJECTIVE: The present study analyzed xylitol concentrations in artificial saliva over time after application of varnishes containing 10% and 20% xylitol. MATERIAL AND METHODS: Fifteen bovine enamel specimens (8x4 mm) were randomly allocated to 3 groups (n=5/group), according to the type of varnish used: 10% xylitol, 20% xylitol and no xylitol (control). After varnish application (4 mg), specimens were immersed in vials containing 500 µL of artificial saliva. Saliva samples were collected in different times (1, 8, 12, 16, 24, 48 and 72 h) and xylitol concentrations were analyzed. Data were assessed by two-way repeated-measures ANOVA (p<0.05). RESULTS: Colorimetric analysis was not able to detect xylitol in saliva samples of the control group. Salivary xylitol concentrations were significantly higher up to 8 h after application of the 20% xylitol varnish. Thereafter, the 10% xylitol varnish released larger amounts of that polyol in artificial saliva. CONCLUSIONS: Despite the results in short-term, sustained xylitol releases could be obtained when the 10% xylitol varnish was used. These varnishes seem to be viable alternatives to increase salivary xylitol levels, and therefore, should be clinically tested to confirm their effectiveness. <![CDATA[<b>Clinical strategies for esthetic excellence in anterior tooth restorations</b>: <b>understanding color and composite resin selection</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200005&lng=en&nrm=iso&tlng=en Direct composite resin restorations have become a viable alternative for patients that require anterior restorative procedures to be integrated to the other teeth that compose the smile, especially for presenting satisfactory esthetic results and minimum wear of the dental structure. Technological evolution along with a better understanding of the behavior of dental tissues to light incidence has allowed the development of new composite resins with better mechanical and optical properties, making possible a more artistic approach for anterior restorations. The combination of the increasing demand of patients for esthetics and the capacity to preserve the dental structure resulted in the development of different incremental techniques for restoring fractured anterior teeth in a natural way. In order to achieve esthetic excellence, dentists should understand and apply artistic and scientific principles when choosing color of restorative materials, as well as during the insertion of the composite resin. The discussion of these strategies will be divided into two papers. In this paper, the criteria for color and material selection to obtain a natural reproduction of the lost dental structures and an imperceptible restoration will be addressed. <![CDATA[<b>Clinical diagnosis of hyposalivation in hospitalized patients</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200006&lng=en&nrm=iso&tlng=en OBJECTIVE: The aim of this study was to evaluate the effectiveness of clinical criteria for the diagnosis of hyposalivation in hospitalized patients. MATERIAL AND METHODS: A clinical study was carried out on 145 subjects (48 males; 97 females; aged 20 to 90 years). Each subject was clinically examined, in the morning and in the afternoon, along 1 day. A focused anamnesis allowed identifying symptoms of hyposalivation, like xerostomia complaints (considered as a reference symptom), chewing difficulty, dysphagia and increased frequency of liquid intake. Afterwards, dryness of the mucosa of the cheecks and floor of the mouth, as well as salivary secretion during parotid gland stimulation were assessed during oral examination. RESULTS: Results obtained with Chi-square tests showed that 71 patients (48.9%) presented xerostomia complaints, with a significant correlation with all hyposalivation symptoms (p <0.05). Furthermore, xerostomia was also significantly correlated with all data obtained during oral examination in both periods of evaluation (p<0.05). CONCLUSION: Clinical diagnosis of hyposalivation in hospitalized patients is feasible and can provide an immediate and appropriate therapy avoiding further problems and improving their quality of life. <![CDATA[<b>Platelet-rich plasma in the treatment of Class II furcation defects</b>: <b>a histometrical study in dogs</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200007&lng=en&nrm=iso&tlng=en OBJECTIVE: This study was designed to evaluate the potential adjunctive benefits of platelet-rich plasma (PRP) when used with guided-tissue regeneration (GTR) and bioactive glass (BG) in the treatment of Class II furcation lesions. MATERIAL AND METHODS: Bilateral Class II furcation lesions were surgically created and allowed to become chronic in the mandibular third premolars of 9 dogs. The defects were randomly assigned to: A) GTR+BG and B) GTR+BG+PRP. Similar defects were created in the maxillary third premolars and received the same treatments after 45 days. Dogs were sacrificed 90 days after the first treatment. The histometric parameters evaluated were: connective tissue adaptation, new cementum, new bone, mineralized bone area, non-mineralized bone area, and residual BG particle area. RESULTS: Data analysis showed a superior length of new cementum and a greater mineralized bone area for group B in both periods (p<0.05). The non-mineralized bone area was greater in the control group (p<0.05) in both periods. CONCLUSION: Within the limits of this study, it can be concluded that the use of PRP in the treatment of Class II furcation defects may enhance the amount of new cementum and provide a more mineralized bone in a shorter period of time. <![CDATA[<b>Influence of tinnitus on pain severity and quality of life in patients with temporomandibular disorders</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200008&lng=en&nrm=iso&tlng=en OBJECTIVE:The aim of this cross-sectional study was to evaluate the relationship among pain intensity and duration, presence of tinnitus and quality of life in patients with chronic temporomandibular disorders (TMD). MATERIAL AND METHODS: Fifty-nine female patients presenting with chronic TMD were selected from those seeking for treatment at the Bauru School of Dentistry Orofacial Pain Center. Patients were submitted to the Research Diagnostic Criteria anamnesis and physical examination. Visual analog scale was used to evaluate the pain intensity while pain duration was assessed by interview. Oral Health Impact Profile inventory modified for patients with orofacial pain was used to evaluate the patients' quality of life. The presence of tinnitus was assessed by self report. The patients were divided into: with or without self report of tinnitus. The data were analyzed statistically using the Student's t-test and Pearson's Chi-square test, with a level of significance of 5%. RESULTS: The mean age for the sample was 35.25 years, without statistically significant difference between groups. Thirty-two patients (54.24%) reported the presence of tinnitus. The mean pain intensity by visual analog scale was 77.10 and 73.74 for the groups with and without tinnitus, respectively. The mean pain duration was 76.12 months and 65.11 months for the groups with and without tinnitus, respectively. The mean OHIP score was 11.72 and 11.74 for the groups with and without tinnitus, respectively. There was no statistically significant difference between groups for pain intensity, pain duration and OHIP scoreS (p>0.05). CONCLUSION: Chronic TMD pain seems to play a more significant role in patient 's quality of life than the presence of tinnitus. <![CDATA[<b>A randomized double-blind clinical trial of posterior composite restorations with or without bevel</b>: <b>1-year follow-up</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200009&lng=en&nrm=iso&tlng=en OBJECTIVE: This randomized double-blind clinical trial compared the performance of posterior composite restorations with or without bevel, after 1-year follow-up. MATERIAL AND METHODS: Thirteen volunteers requiring at least two posterior composite restorations were selected. Twenty-nine cavities were performed, comprising 14 without bevel (butt joint) and 15 with bevel preparation of the enamel cavosurface angle. All cavities were restored with simplified adhesive system (Adper Single Bond) and composite resin (Filtek P60). A halogen light curing unit was used through the study. Restorations were polished immediately. Analysis was carried out at baseline, after 6 months and after 1 year by a calibrated evaluator (Kappa), according to the FDI criteria. Data were statistically analyzed by Mann-Whitney test (p <0.05). RESULTS: Beveled and non-beveled cavities performed similarly after 1 year follow-up, regarding to fractures and retention, marginal adaptation, postoperative hypersensitivity, recurrence of caries, surface luster and anatomic form. However, for surface and marginal staining, beveled cavities showed significantly better performance (p<0.05) than butt joint restorations. CONCLUSIONS: It was concluded that the restorations were acceptable after 1 year, but restorations placed in cavities with marginal beveling showed less marginal staining than those placed in non-beveled cavities. <![CDATA[<b>Differential expression of salivary glycoproteins in aggressive and chronic periodontitis</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200010&lng=en&nrm=iso&tlng=en OBJECTIVES:The aim of this study was to compare the pattern of secretion and the expression of mucin glycoprotein-2 (MG2) and lactoferrin in individuals with or without periodontitis. MATERIAL AND METHODS: Five individuals with aggressive periodontitis (APG), 5 with generalized chronic periodontitis (CPG) and 5 without periodontitis (CG) were enrolled after informed consent. Non-stimulated and stimulated submandibular and sublingual saliva was collected and samples analyzed by Western blot probed with specific antibodies. RESULTS: Stimulated and non-stimulated salivary flow rates did not differ among groups. Western blot analysis revealed that stimulation led to: an increase in MG2 expression in all groups, and to lactoferrin expression in APG and CPG. In non-stimulated saliva, CG exhibited the highest expression of both glycoproteins. In stimulated saliva, CG exhibited the highest expression of MG2, whereas APG the highest of lactoferrin. CONCLUSIONS: The pattern of secretion of MG2 and lactoferrin in health and disease is complex. Although the present study analyzed samples from a limited number of participants, the reduced expression of MG2 and lactoferrin in APG and CPG under non-stimulated condition, the predominant circumstance of salivary secretion during the day, suggests that these salivary constituents may play a role in the etiopathogenesis of these diseases. <![CDATA[<b>Effectiveness of different carbamide peroxide concentrations used for tooth bleaching</b>: <b>an <i>in vitro</i> study</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200011&lng=en&nrm=iso&tlng=en OBJECTIVES: This in vitro study evaluated the effectiveness of three carbamide peroxide concentrations used for tooth bleaching treatments. MATERIAL AND METHODS: Sixty bovine dental slabs (6x6x3 mm) were obtained, sequentially polished, submitted to artificial staining (baseline) and randomized into four groups (n=15), according to the bleaching agent concentration: distilled water (control), 10% (CP10), 16% (CP16) or 37% (CP37) carbamide peroxide. CP10 and CP16 were covered with 0.2 mL of the respective bleaching gels, which were applied on enamel surface for 4 h/day during two weeks. Samples of CP37 were covered with 0.2 mL of the bleaching gel for 20 min. The gel was light activated by two 40-s applications spaced by 10-min intervals. The gel was renewed and applied 3 times per clinical session. This cycle was repeated at 3 sessions with 5 days of interval between them. Tooth shade evaluations were done with a digital spectrophotometer at T0 (baseline), T1 (after 1-week of treatment) and T2 (1-week post-bleaching). Tooth shade means were statistically analyzed by Kruskal-Wallis and Friedman's tests and color parameters were analyzed by two-way ANOVA and Tukey's test (p<0.05). RESULTS: At T1 and T2 evaluations, tooth shade was significantly lighter than at baseline for all treatment groups, considering the color parameters ΔL*, Δa*, Δb*, ΔE* (p<0.001) or tooth shade means (p<0.001). CP37 group showed lower shade mean change than CP10 and CP16 at T1 (p<0.01), but this difference was not statistically significant at T2 (p&gt;0.05). CONCLUSIONS: One week after the end of the treatment, all carbamide peroxide concentrations tested produced similar tooth color improvement. <![CDATA[<b>Two-year clinical evaluation of three adhesive systems in non-carious cervical lesions</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200012&lng=en&nrm=iso&tlng=en OBJECTIVES: Adhesive systems are continuously being introduced to Dentistry, unfortunately often without sufficient clinical validation. The aim of this study was to evaluate the clinical performance of cervical restorations done with three different adhesive systems. MATERIAL AND METHODS: 158 non-carious cervical lesions of 23 patients were restored with a nanofilled composite resin (Filtek Supreme, 3M/ESPE) combined with Single Bond (3M/ESPE, group SI), Clearfil SE (Kuraray Medical Inc., group CL) and Xeno III (De Trey Dentsply, group XE). In groups SI-B, CL-B and XE-B, the outer surface of the sclerotic dentin was removed by roughening with a diamond bur before application of the respective adhesive systems. In groups CL-BP and XE-BP, after removal of the outer surface of the sclerotic dentin with the bur, the remaining dentin was etched with 37% phosphoric acid and the self-etch adhesive systems Clearfil SE and Xeno III were applied, respectively. Lesions were evaluated at baseline, and restorations after 3 months, 1 year and 2 years using modified USPHS criteria. RESULTS: After 2 years, no significant difference was found between the retention rates of the groups (p &gt;0.05). Although groups CL and SI showed significantly better marginal adaptation than group XE (p<0.05) at 2 years, no significant difference was found between the marginal adaptation of the groups SI-B, CL-B and XE-B (p&gt;0.05). After 2 years no significant difference was observed among the marginal staining results of all groups (p&gt;0.05). CONCLUSION: Although all adhesive systems showed similar retention rates, Clearfil SE and Single Bond showed better marginal adaptation than Xeno III after 2 years of follow-up. <![CDATA[<b>Color stability, surface roughness and microhardness of composites submitted to mouthrinsing action</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200013&lng=en&nrm=iso&tlng=en OBJECTIVE:The purpose of this study was to evaluate the effect of mouth rinse solutions on color stability, surface roughness and microhardness of two composite resins. MATERIAL AND METHODS: Fifty test specimens of each composite (Filtek Z250 and Z350; 3M ESPE) were made using a teflon matrix (12x2 mm). Color, surface roughness and Knoop microhardness baseline measurements of each specimen were made and specimens (n=10) were immersed in 5 mouth rinse solutions: G1: distilled water (control), G2: Plax Classic, G3: Plax alcohol-free; G4: Periogard, and G5: Listerine. Final measurements of color, roughness and microhardness were performed and the results submitted to statistical analysis (2-way ANOVA, Bonferroni ’s test; p<0.05). RESULTS: The most significant color change was observed for Z250 when immersed in Listerine (p<0.05). Z350 showed greater color change when immersed in Plax alcohol-free (p<0.05), but with no significant difference for Listerine (p&gt;0.05). With regard to roughness, both composites showed significant changes when immersed in Listerine in comparison with Plax alcohol-free (p<0.05). Microhardness of Z350 was shown to be significantly changed when the composite was immersed in Plax alcohol-free (p<0.05). CONCLUSION: Composite changes depended on the material itself rather than the mouth rinse solution used. <![CDATA[<b>Interference of partial visual analysis of root filling quality and apical status on retreatment decisions</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200014&lng=en&nrm=iso&tlng=en OBJECTIVE: The presence of periapical radiolucency has been used as a criterion for endodontic treatment failure. However, in addition to the inherent limitations of radiographic examinations, radiographic interpretations are extremely subjective. Thus, this study investigated the effect of partial analysis of root filling quality and periapical status on retreatment decisions by general dentists. MATERIAL AND METHODS: Twelve digitalized periapical radiographs were analyzed by 10 observers. The study was conducted at three time points at 1-week intervals. Radiographs edited with the Adobe Photoshop CS4 software were analyzed at three time points: first, only root filling quality was analyzed; second, only the periapical areas of the teeth under study were visualized; finally, observers analyzed the unedited radiographic image. Spearman ’s coefficient was used to analyze the correlations between the scores assigned when the periapical area was not visible and when the unedited radiograph was analyzed, as well as between the scores assigned when root fillings where not visible and when the unedited radiograph was analyzed. Sensitivity, specificity, positive and negative predictive values between partial images and unedited radiographs were also used to analyze retreatment decisions. The level of significance was set at 5%. RESULTS: The visualization of the root filling on the unedited radiograph affected the interpretation of the periapical status and the technical quality of the fillings has a greater influence on the general dentist’s decision to prescribe endodontic retreatment than the periapical condition. CONCLUSION: In order to make endodontic diagnosis, radiographic interpretation process should not only emphasize technical aspects, but also consider biological factors. <![CDATA[<b>Degree of conversion of nanofilled and microhybrid composite resins photo-activated by different generations of LEDs</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200015&lng=en&nrm=iso&tlng=en OBJECTIVE:This study aimed at evaluating the degree of conversion (DC) of four composite resins, being one nanofilled and 3 microhybrid resins, photo-activated with second- and third-generation light-emitting diodes (LEDs). MATERIAL AND METHODS: Filtek TM Z350 nanofilled composite resins and Amelogen® Plus, Vit-l-escenceTM and Opallis microhybrid resins were photo-activated with two second-generation LEDs (Radii-cal and Elipar Free LightTM 2) and one third-generation LED (Ultra-Lume LED 5) by continuous light mode, and a quartz halogen-tungsten bulb (QHT, control). After 24 h of storage, the samples were pulverized into fine powder and 5 mg of each material were mixed with 100 mg of potassium bromide (KBr). After homogenization, they were pressed, which resulted in a pellet that was evaluated using an infrared spectromer (Nexus 470, Thermo Nicolet) equipped with TGS detector using diffuse reflectance (32 scans, resolution of 4 cm-1) coupled to a computer. The percentage of unreacted carbon-carbon double bonds (% C=C) was determined from the ratio of absorbance intensities of aliphatic C=C (peak at 1637 cm-1) against internal standard before and after curing of the specimen: aromatic C-C (peak at 1610 cm-1). RESULTS: The ANOVA showed a significant effect on the interaction between the light-curing units (LCUs) and the composite resins (p<0.001). The Tukey’s test showed that the nanofilled resin (FiltekTM Z350) and Opallis when photo-activated by the halogen lamp (QTH) had the lowest DC compared with the other microhybrid composite resins. The DC of the nanofilled resin (FiltekTM Z350) was also lower using LEDs. The highest degrees of conversion were obtained using the third-generation LED and one of second-generation LEDs (Elipar Free LightTM 2). CONCLUSIONS: The nanofilled resin showed the lowest DC, and the Vit-l-escenceTM microhybrid composite resin showed the highest DC. Among the LCUs, it was not possible to establish an order, even though the second-generation LED Radii-cal provided the lowest DC. <![CDATA[<b>Effect of obesity on alveolar bone loss in experimental periodontitis in Wistar rats</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200016&lng=en&nrm=iso&tlng=en Obesity has been linked to higher inflammatory status and periodontal breakdown. OBJECTIVE: The purpose of this study was to investigate the effect of obesity on alveolar bone loss in experimental periodontitis in rats. MATERIAL AND METHODS: Twenty-four female Wistar rats were randomly divided into two groups: obese (n=13), which were fed with "cafeteria diet" (CAF diet - high amounts of sucrose and fat) for 90 days in order to gain weight, and non-obese (n=11) regularly fed rats. Ligature-induced experimental periodontitis was created in all animals. Body weight differed statistically between obese and non-obese groups (277.59 and 223.35 g, respectively) at the moment of the ligature placement. Morphometric registration of alveolar bone loss was carried out after 30 days of ligature placement to determine the effect of obesity on the progression of experimental periodontitis. RESULTS: Intra-group comparisons showed significantly higher alveolar bone loss mean values in maxillary teeth with ligature (P<0.05). Alveolar bone loss [mean (SD), mm] was not statistically different between obese and non-obese groups [0.71 (0.09) and 0.65 (0.07) mm, respectively]. However, when palatal sides are analyzed separately, obese group presented significantly higher alveolar bone loss (P<0.05) as compared to non-obese [0.68 (0.12) and 0.53 (0.13) mm, respectively]. CONCLUSIONS: In spite of the weak differences, it is possible to conclude that the progression of alveolar bone loss in ligature-induced periodontitis can be potentially influenced by body weight in rats. <![CDATA[<b>Alveolar bone healing process in spontaneously hypertensive rats (SHR)</b>: <b>A radiographic densitometry study</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200017&lng=en&nrm=iso&tlng=en Hypertension is one of the most important public health problems worldwide. If undiagnosed or untreated, this pathology represents a systemic risk factor and offers unfavorable conditions for dental treatments, especially those requiring bone healing. Objectives: The purpose of this study was to demonstrate, by analysis of bone mineral density (BMD), that the alveolar bone healing process is altered in spontaneously hypertensive rats (SHRs). Material and Methods: Wistar rats and SHRs were submitted to extraction of the upper right incisor and were euthanized 7, 14, 21, 28 and 42 days after surgery. Right maxillae were collected, radiographed and analyzed using Digora software. BMD was expressed as minimum (min), middle (med) and maximum (max) in the medium (MT) and apical (AT) thirds of the dental alveolus. Results: The results were compared across days and groups. Wistar showed difference in med and max BMD in the MT between 7 and 28 and also between 14 and 28 days. The AT exhibited significant difference in med and min BMD between 7 and 28 days, as well as difference in min BMD between 28 and 42 days. SHRs showed lower med BMD in the MT at 28 days when compared to 21 and 42 days. Differences were observed across groups in med and min BMD at day 28 in the MT and AT; and in max BMD at 14, 21 and 42 days in the MT. Conclusions: These results suggest that the alveolar bone healing process is delayed in SHRs comparing with Wistar rats. <![CDATA[<b>Clinical evaluation of the failure rates of metallic brackets</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200018&lng=en&nrm=iso&tlng=en OBJECTIVES: The aim of this study was to evaluate in vivo the bonding of metallic orthodontic brackets with different adhesive systems. MATERIAL AND METHODS: Twenty patients (10.5-15.1 years old) who had sought corrective orthodontic treatment at a University Orthodontic Clinic were evaluated. Brackets were bonded from the right second premolar to the left second premolar in the upper and lower arches using: Orthodontic Concise, conventional Transbond XT, Transbond XT without primer, and Transbond XT associated with Transbond Plus Self-etching Primer (TPSEP). The 4 adhesive systems were used in all patients using a split-mouth design; each adhesive system was used in one quadrant of each dental arch, so that each group of 5 patients received the same bonding sequence. Initial archwires were inserted 1 week after bracket bonding. The number of bracket failures for each adhesive system was quantified over a 6-month period. RESULTS: The number of debonded brackets was: 8- Orthodontic Concise, 2- conventional Transbond XT, 9- Transbond XT without primer, and 1- Transbond XT + TPSEP. By using the Kaplan-Meier methods, statistically significant differences were found between the materials (p=0.0198), and the Logrank test identified these differences. Conventional Transbond XT and Transbond XT + TPSEP adhesive systems were statistically superior to Orthodontic Concise and Transbond XT without primer (p<0.05). There was no statistically significant difference between the dental arches (upper and lower), between the dental arch sides (right and left), and among the quadrants. CONCLUSIONS: The largest number of bracket failures occurred with Orthodontic Concise and Transbond XT without primer systems and few bracket failures occurred with conventional Transbond XT and Transbond XT+TPSEP. More bracket failures were observed in the posterior region compared with the anterior region. <![CDATA[<b>Internal fit of two all-ceramic systems and metal-ceramic crowns</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200019&lng=en&nrm=iso&tlng=en OBJECTIVES: The aim of this study was to investigate the internal fit (IF) of glass-infiltrated alumina (ICA - In-Ceram Alumina), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP - IPS e.max ZirCAD), and metal-ceramic (MC - Ni-Cr alloy) crowns. MATERIAL AND METHODS: Sixty standardized resin-tooth replicas of a maxillary first molar were produced for crown placement and divided into 3 groups (n=20 each) according to the core material used (metal, ICA or Y-TZP). The IF of the crowns was measured using the replica technique, which employs a light body polyvinyl siloxane impression material to simulate the cement layer thickness. The data were analyzed according to the surfaces obtained for the occlusal space (OS), axial space (AS) and total mean (TM) using two-way ANOVA with Tukey ’s multiple comparison test (p<0.05). RESULTS: No differences among the different areas were detected in the MC group. For the Y-TZP and ICA groups, AS was statistically lower than both OS and TM. No differences in AS were observed among the groups. However, OS and TM showed significantly higher values for ICA and Y-TZP groups than MC group. Comparisons of ICA and Y-TZP revealed that OS was significantly lower for Y-TZP group, whereas no differences were observed for TM. CONCLUSIONS: The total mean achieved by all groups was within the range of clinical acceptability. However, the metal-ceramic group demonstrated significantly lower values than the all-ceramic groups, especially in OS. <![CDATA[<b>Assessment and management of oral health in liver transplant candidates</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200020&lng=en&nrm=iso&tlng=en Liver transplantation has become a standard treatment for end-stage liver disease and the number of recipients has grown rapidly in the last few years. Dental care during pre-transplant workup is important to reduce potential sources of infection in the drug-induced immunosuppression phase of liver transplantation. Objectives: The objectives of this study were to document the prevalence of oral abnormalities in patients on a liver transplant waiting list presenting to an urban dental school clinic, discuss the appropriate dental treatment according their systemic conditions and compare their oral manifestations with those of healthy individuals. Material and Methods: A pilot study was conducted involving 16 end-stage liver disease individuals (study group- SG) attending the Special Care Dentistry Center of the University of São Paulo and 16 control individuals (control group- CG) with no liver diseases, receiving dental care at the Dental School of the University of São Paulo. These individuals were assessed for their dental status (presence of oral disease or abnormalities), coagulation status, and dental treatment indications. Results: The patients from SG exhibited a greater incidence of oral manifestations compared with CG (p=0.0327) and were diagnosed with at least one oral disease or condition that required treatment. Coagulation abnormalities reflecting an increased risk of bleeding were found in 93.75% of the patients. However, no bleeding complications occurred after dental treatment. Conclusions: The patients with chronic liver diseases evaluated in this study exhibited a higher incidence of oral manifestations compared with the control group and had at least one oral disease or abnormality which required dental treatment prior to liver transplantation. Careful oral examination and evaluation of the patient, including laboratory tests, will ensure correct oral preparation and control of oral disease prior to liver transplantation. <![CDATA[<b>Effect of light sources and curing mode techniques on sorption, solubility and biaxial flexural strength of a composite resin</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200021&lng=en&nrm=iso&tlng=en Adequate polymerization plays an important role on the longevity of the composite resin restorations. OBJECTIVES: The aim of this study was to evaluate the effect of light-curing units, curing mode techniques and storage media on sorption, solubility and biaxial flexural strength (BFS) of a composite resin. MATERIAL AND METHODS: Two hundred and forty specimens were made of one composite resin (Esthet-X) in a stainless steel mold (2 mm x 8 mm Ø), and divided into 24 groups (n=10) established according to the 4 study factors: light-curing units: quartz tungsten halogen (QTH) lamp and light-emitting diodes (LED); energy densities: 16 J/cm² and 20 J/cm²; curing modes: conventional (CM) and pulse-delay (PD); and permeants: deionized water and 75% ethanol for 28 days. Sorption and solubility tests were performed according to ISO 4049:2000 specifications. All specimens were then tested for BFS according to ASTM F394-78 specification. Data were analyzed by three-way ANOVA followed by Tukey, Kruskal-Wallis and Mann-Whitney tests (α=0.05). RESULTS: In general, no significant differences were found regarding sorption, solubility or BFS means for the light-curing units and curing modes (p&gt;0.05). Only LED unit using 16 J/cm² and PD using 10 s produced higher sorption and solubility values than QTH. Otherwise, using CM (16 J/cm²), LED produced lower values of BFS than QTH (p<0.05). 75% ethanol permeant produced higher values of sorption and solubility and lower values of BFS than water (p<0.05). CONCLUSION: Ethanol storage media produced more damage on composite resin than water. In general the LED and QTH curing units using 16 and 20 J/cm² by CM and PD curing modes produced no influence on the sorption, solubility or BFS of the tested resin. <![CDATA[<b>Influence of combined oral contraceptives on the periodontal condition</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200022&lng=en&nrm=iso&tlng=en Most studies investigating the impact of oral contraceptives have been performed some years ago, when the level of sexual hormones was greater than the actual formulations. Objective: The aim of this study was to evaluate the effects of current combined oral contraceptives (COC) on periodontal tissues, correlating the clinical parameters examined with the total duration of continuous oral contraceptive intake. Material and methods: Twenty-five women (19-35 years old) taking combined oral contraceptives for at least 1 year were included in the test group. The control group was composed by 25 patients at the same age range reporting no use of hormone-based contraceptive methods. Clinical parameters investigated included pocket probing depth (PD), clinical attachment level (CAL), sulcular bleeding index (SBI) and plaque index (Pl.I). Data were statistically evaluated by unpaired t test, Pearson’s correlation test and Spearman’s correlation test. Results: The test group showed increased PD (2.228±0.011 x 2.154±0.012; p<0.0001) and SBI (0.229±0.006 x 0.148±0.005, p<0.0001) than controls. No significant differences between groups were found in CAL (0.435±0.01 x 0.412±0.01; p=0.11). The control group showed greater Pl.I than the test group (0.206±0.007 x 0.303±0.008; p<0.0001). No correlation between the duration of oral contraceptive intake, age and periodontal parameters was observed. Conclusions: These findings suggest that the use of currently available combined oral contraceptives can influence the periodontal conditions of the patients, independently of the level of plaque accumulation or total duration of medication intake, resulting in increased gingival inflammation. <![CDATA[<b>Effect of root canal filling materials on dimensions of cone-beam computed tomography images</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200023&lng=en&nrm=iso&tlng=en OBJECTIVE:To evaluate the discrepancy of root canal filling (RCF) measurements obtained from original root specimens and cone-beam computed tomography (CBCT) images. MATERIAL AND METHODS: Seventy-two human maxillary anterior teeth were prepared up to an ISO #50 K-File 1 mm short of the apical foramen. Thus, the teeth were randomly divided into 8 groups, according to the root canal filling material: Sealapex ®, Sealapex®+gutta-percha points, Sealer 26®, Sealer 26®+gutta-percha points, AH PlusTM, AH PlusTM+gutta-percha points, Grossman Sealer, and Grossman Sealer+gutta-percha points. After root canal preparation and RCF, CBCT scans were acquired and the specimens were sectioned in axial, sagittal and coronal planes. The RCF measurements were obtained in different planes and thicknesses to determine the discrepancy between the original root specimens (using a digital caliper) and the CBCT images (using the scanner’s proprietary software). One-way analysis of variance and Tukey tests were used for statistical analyses. The significance level was set at α=5%. RESULTS: Measurements of the different endodontic filling materials were 9% to 100% greater on the CBCT images than on the original root specimens. Greater RCF dimensions were found when only sealers were used, with statistically significant difference among the groups. CONCLUSIONS: RCF dimensions were greater on CBCT images than on the original root specimens, especially when only sealer was used. <![CDATA[<b>Rehabilitative treatment of cleft lip and palate</b>: <b>experience of the Hospital for Rehabilitation of Craniofacial Anomalies - USP (HRAC-USP) - Part 2: Pediatric Dentistry and Orthodontics</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200024&lng=en&nrm=iso&tlng=en The aim of this article is to present the pediatric dentistry and orthodontic treatment protocol of rehabilitation of cleft lip and palate patients performed at the Hospital for Rehabilitation of Craniofacial Anomalies - University of São Paulo (HRAC-USP). Pediatric dentistry provides oral health information and should be able to follow the child with cleft lip and palate since the first months of life until establishment of the mixed dentition, craniofacial growth and dentition development. Orthodontic intervention starts in the mixed dentition, at 8-9 years of age, for preparing the maxillary arch for secondary bone graft procedure (SBGP). At this stage, rapid maxillary expansion is performed and a fixed palatal retainer is delivered before SBGP. When the permanent dentition is completed, comprehensive orthodontic treatment is initiated aiming tooth alignment and space closure. Maxillary permanent canines are commonly moved mesially in order to substitute absent maxillary lateral incisors. Patients with complete cleft lip and palate and poor midface growth will require orthognatic surgery for reaching adequate anteroposterior interarch relationship and good facial esthetics. <![CDATA[<b>Surgical management of dentigerous cyst and keratocystic odontogenic tumor in children</b>: <b>a conservative approach and 7-year follow-up</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200025&lng=en&nrm=iso&tlng=en Dentigerous cyst (DC) is one of the most common odontogenic cysts of the jaws and rarely recurs. On the other hand, keratocystic odontogenic tumor (KCOT), formerly known as odontogenic keratocyst (OKC), is considered a benign unicystic or multicystic intraosseous neoplasm and one of the most aggressive odontogenic lesions presenting relatively high recurrence rate and a tendency to invade adjacent tissue. Two cases of these odontogenic lesions occurring in children are presented. They were very similar in clinical and radiographic characteristics, and both were treated by marsupialization. The treatment was chosen in order to preserve the associated permanent teeth with complementary orthodontic treatment to direct eruption of the associated permanent teeth. At 7-years of follow-up, none of the cases showed recurrence. <![CDATA[<b>Posterior crossbite - treatment and stability</b>]]> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572012000200026&lng=en&nrm=iso&tlng=en Posterior crossbite is defined as an inadequate transversal relationship of maxillary and mandibular teeth. Even when eliminating the etiologic factors, this malocclusion does not have a spontaneous correction, and should be treated with maxillary expansion as early as possible. This treatment aims at providing a better tooth/skeletal relationship, thereby improving masticatory function, and establishing a symmetrical condyle/fossa relationship. Should posterior crossbite not be treated early, it may result in skeletal changes, demanding a more complex approach. Additionally, an overcorrection expansion protocol should be applied in order to improve the treatment stability. Although the literature has reported a high rate of relapse after maxillary expansion, the goal of this study was to demonstrate excellent stability of the posterior crossbite correction 21 years post treatment.