Resumo em Inglês:

AIM: To assess the combined use of tetracycline (TTC) and ethylenediaminetetraacetic acid (EDTA) on clot formation, considering that EDTA may neutralize TTC acidity. METHODS: Planed human tooth roots were treated with saline solution, EDTA, TTC and their combination (EDTA followed by TTC and TTC before EDTA). Fresh human blood was applied on the conditioned surfaces to check clot adhesion and stabilization. A previously calibrated (kappa = 0.93) and blinded examiner scored scanning electron micrographs of the samples. Statistical analyses were performed using one-way ANOVA and Tukey's test. RESULTS: Application of TTC before EDTA presented the best results with the highest number of cells adhered to the root surface (p=0.046). Use of EDTA alone and EDTA before TTC disturbed clot stabilization when compared to control group (p<0.01). CONCLUSIONS: The use of TTC before EDTA seems to be able to keep blood cells viable to establish an organized clot and could be used by clinicians together with the conventional mechanical root scaling and planing.

Resumo em Inglês:

AIM: To evaluate the microleakage at the implant-abutment (I-A) interface of Morse tapered implants inoculated with different volumes of bacterial suspension. METHODS: Morse tapered I-A sets were selected and divided in two groups depending on the type of abutment: passing screw (PS) and solid (S), and then subdivided into four subgroups (n=6) according to the suspension volume: PS1: 0.1 µL; PS3: 0.3 µL; PS5: 0.5 µL; PS7: 0.7 µL; S1: 0.1 µL; S3: 0.>3 µL; S5: 0.5 µL and S7: 0.7 µL. A control test was performed to verify the presence of external contamination during the inoculation and the implants were incubated for microbiological analysis. The microleakage was evaluated every 24 h for 7 days by the clarity of solution. After this period, the implants were disassembled for confirmation of bacterial viability. RESULTS: All the specimens with 0.7 µL and one sample of S5 presented turbidity in the control test indicating external contamination, and were excluded from the study. After 7 days of observation, none of the specimens presented positive results for microleakage and the bacterial viability was confirmed in all specimens. The 0.1 µL and 0.3 µL volumes did not present bacterial microleakage, meaning that these volumes may be inadequate for analysis. CONCLUSIONS: None of the sets evaluated showed bacterial microleakage at the I-A interface and the volume of 0.7 µL exceeded the internal capacity of the implants.

Resumo em Inglês:

AIM: To evaluate changes in pharyngeal airway space (nasopharynx and oropharynx), soft palate and lingual vallecula after maxillary advancement surgery and maxillary advancement and mandibular setback surgery (bimaxillary surgery). METHODS: Twenty Class III adult patients were included in the study. Ten patients were treated with maxillary advancement and ten with bimaxillary surgery (maxillary advancement and mandibular setback). Cephalometric landmark measurements were recorded at 3 different time intervals: pre-surgical, post-surgical and six months after surgery. Data collected were subjected to one-way ANOVA (p<0.05). RESULTS: Nasopharyngeal airway space increased after maxillary advancement and decreased after bimaxillary surgery. There was increase in oropharyngeal dimensions in the region around the uvula and loss of space for lingual vallecula, while in Group 2 there was diminished space for both uvula and vallecula. The uvula and vallecula were moved forward in Group 1, whereas these structures were moved in the posterior direction in Group 2. CONCLUSIONS: After maxillary advancement surgery there was an increased in space in the nasopharyngeal region. The oropharyngeal region related to the uvula presented an increase in space, whereas there was a reduction in relation to the lingual vallecula. The uvula and lingual vallecula were moved forward. Bimaxillary surgery promoted a reduction in the nasopharyngeal and oropharyngeal regions as regards both the uvula and lingual vallecula. The uvula and lingual vallecula were moved in the posterior direction.

Resumo em Inglês:

AIM: To evaluate medical records from patients who had maxillofacial infections between August 2002 and May 2010. METHODS: Analysis of 157 patients' data looking for epidemiology, causes of the infection, type of treatment established and complications. RESULTS: 113 patients had odontogenic infections and 44 had non-odontogenic infections. The white ethnicity was the most affected (64.33%), prevailing the men (53.5%). The odontogenic infections occurred mostly at the mandible (55.74%), involving the posterior teeth (82%). Dental decay was the main etiology (90.90%). The most affected facial anatomic region was the submandibular (42.85%). Surgical treatment was required in 76% of the cases. CONCLUSIONS: Maxillofacial infections should be treated as soon as possible. Even without culture and antibiogram results, it was possible to treat the infection and to reestablish tissue function.

Resumo em Inglês:

AIM: To assess which slice inclination would be more accurate in measuring sites for implant placement: the oblique or the orthoradial slice. METHODS: Five regions of eight edentulous mandibles were selected (incisor, canine, premolar, first molar and second molar). The mandibles were scanned with a Next Generation i-CAT CBCT unit. Two previously calibrated oral radiologists performed vertical measurements in all the selected regions using both the oblique and orthoradial slices. The mandibles were sectioned in all the evaluated regions in order to obtain the gold standard. The Wilcoxon signed rank test compared the measurements obtained in the oblique and orthoradial slices with the gold standard. RESULTS: The bone height measurements for the first and second molar regions using the orthoradial slices were statistically different from the gold standard. CONCLUSIONS: Using the orthoradial slices to obtain cross-sectional images may offer insufficient accuracy for implant placement in the posterior region.

Resumo em Inglês:

AIM: To evaluate changes in blood pressure and heart rate in patients undergoing dental implant procedures, considering the dental setting as the main variable. METHODS: Fifty-five patients who underwent dental implant surgery were evaluated. Thirty-seven were treated at a university clinic and 18 were treated at a private office. Blood pressure and heart rate were measured at the following time-points: at the appointment prior to surgery (T0), immediately before the surgical procedure (T1), during anesthesia (T2), during implant installation (T3), immediately after the surgical procedure (T4) and at the first follow-up appointment after surgery (T5). The data were analyzed by two-way analysis of variance and Student's t-test. RESULTS : The university clinic patients had an increase in heart rate at T5 (t53=2.62, p<0.05) compared with private office patients. Systolic blood pressure in university clinic patients was higher at T2 (t53=2.86, p<0.01), T3 (t53=2.64, p<0.05), and T4 (t53=3.15, p<0.01). Diastolic blood pressure at T2 (t53=3.15, p<0.01) and T3 (t53=3.86, p<0.01) were also higher in university clinic patients. CONCLUSIONS : These results suggest that the dental setting is a relevant factor when planning dental implant surgery.

Resumo em Inglês:

AIM: To evaluate the bond strength to root dentin of three root canal sealers: a mineral trioxide aggregate (MTA)-based sealer (MTA Fillapex(r)), an epoxy resin-based sealer (AH Plus(r)), and a zinc oxide eugenol-based sealer (EndoFill(r)). METHODS: Thirty extracted single-root human teeth of similar sizes and circular canals were prepared using #3 and #2 Gates Glidden drills in the cervical portion of the canal and K3(r) rotary instruments to a size #25/0.06 to working length. Irrigation with 0.5 mL 2% chlorhexidine gel was used before and 1 mL saline after each instrument.The smear layer was removed with 3 mL 17% EDTA for 3 min. The samples were sectioned horizontally into eight 1±0.1 mm-thick serial slices and then the push-out test was carried out. Two-way analysis of variance (ANOVA) and the post-hoc Tukey test were used for the analysis of the data with a significance level of 5%. RESULTS: AH Plus presented significantly higher bond strengths (p<0.05) than the other sealers, while MTA Fillapex showed the lowest bond strengths (p<0.05). CONCLUSIONS: The present study concluded that EndoFill(r) sealer and MTA FillApex(r) core combination were not superior to AH Plus(r) sealer and gutta-percha core combination.

Resumo em Inglês:

AIM: To introduce a modification of the reline impression technique (MRIT), and compare the dimensional changes of impressions obtained by MRIT and by conventional reline impression technique (CRIT). METHODS: An acrylic resin tablet was milled by a CAD-CAM system to simulate three abutments (A, B and C) with different distances among them. The abutments were molded using both impression techniques. For MRIT, before completing the putty silicone polymerization, the relieve procedure was made by compression and it was immediately repositioned to complete the polymerization. Impressions were stored dry at room temperature for different periods (immediately, 1 h, 2 days and 7 days). The distances were obtained by scanning. The differences between the impressions and their respective matrix reference measurements were calculated to determine the dimensional changes. Data were subjected to ANOVA and Tukey's test (p<0.05). RESULTS: For AB and BC distances, there was no statistically significant difference between CRIT and MRIT (p=0.0597 and p=0.2167, respectively). For AC, there was statistically significant difference between the techniques for the immediate storage time (p=0.006). In general, for CRIT the material showed expansion, while for MRIT it showed contraction. CONCLUSIONS: It was verified that the addition silicon impressions obtained by both impression techniques showed dimensional stability, except for the immediate time-point.

Resumo em Inglês:

AIM: To investigate the effect of the cooling rate on flexural strength of monolayer and bilayer porcelain/zirconia (Y-TZP) bars. METHODS: Forty-five specimens were made for each design group: (PM) monolithic specimens of veneer porcelain Vita VM9 (Vita, Germany); (ZM) monolithic specimens of zirconia (ZiHP; ProtMat, Brazil); (PB) bilayer specimens zirconia/porcelain with porcelain on lower surface; and (ZB) bilayer specimens porcelain/zirconia with zirconia on lower surface. Each group was cooled by three different methods after porcelain sintering: slow specimens were cooled inside the turned-off furnace; normal specimens were removed from the furnace and cooled in air at room temperature; and fast specimens were removed from the furnace at 910°C and cooled by compressed air for 10 s. Specimens were polished and flexural strength was measured in water at 37 °C (n=15). Maximum load at fracture was recorded, and equations for simple (monolayer) and composite (bilayer) structures were used to calculate the flexural strength. RESULTS were analyzed using one-way ANOVA (p<0.05) and Tukey test separately for each design. RESULTS: The results of one-way ANOVA were statistically significant only for the PB group. The post-hoc Tukey test showed the highest flexural strength for fast cooling and the lowest for slow cooling; the normal cooling was statistically similar to both. CONCLUSIONS: Cooling methods affected only the flexural strength of bilayer specimens with porcelain on low surface (under tension) when the slow cooling method was used.

Resumo em Inglês:

AIM: To evaluate the staining of esthetic orthodontic brackets by plaque disclosing solutions. METHODS: Two types of brackets manufactured by GAC/DENTSPLY(r) were evaluated: ceramic (n=30) and polycarbonate (n=30). The brackets were divided into 6 groups. Two control groups (n=6) were immersed in absolute ethanol: GI - ceramic brackets and GII - polycarbonate brackets. Four experimental groups (n=12) were immersed in different plaque disclosing solutions: GIII (ceramic brackets) and GIV (polycarbonate brackets) were immersed in Replak(r); GV (ceramic brackets) and GVI (polycarbonate brackets) were immersed in Replasul "S"(r). Relative quantitative analysis of the influence of plaque disclosing tablets on bracket staining was performed using reflectance spectrophotometry of stain deposition. Exploratory analysis of the data was performed using Analysis of Variance (ANOVA) in a 2x2 factorial setup (bracket x immersion) with additional treatments (controls). RESULTS: The results demonstrated that the ceramic brackets presented the highest amount of staining when Replasul "S"(r) was used (pd"0.05). However, when Replak(r) was used, no statistically significant difference was found in comparison with the control group (p>0.05). For polycarbonate brackets, staining was detected for both disclosing solutions (p>0.05). CONCLUSIONS: The disclosing solutions caused stain formation on polycarbonate brackets and, under the tested conditions, use of Replak(r) on ceramic brackets did not cause staining.

Resumo em Inglês:

AIM: To identify the prevalence of dental caries in inland Brazilian adolescents, and to analyze the influence of socio-demographic and clinical variables, and access to dental service on caries experience. METHODS: This study had a non-probabilistic sample comprising 504 adolescents aged 12 years, attending public schools in the city of Nova Friburgo, mountain region of Rio de Janeiro, Brazil. The World Health Organization (WHO, 1997) criterion was used by previously calibrated examiners to report dental caries. Variables were obtained by means of a semi-structured questionnaire applied to the adolescents' parents. RESULTS: The D3MFT mean was 1.90 and the Significant Caries (SIC) Index was 4.54, mainly represented by the carious component. Multiple logistic regression analysis revealed that parents with over 8 years of schooling (OR=0.579), absence of pain (OR=0.396) and not visiting the dentist (OR=0.270) might suggest protective factors against the disease; the possible risk factors were male gender (OR=1.982) and pain, extraction and others were reasons for consultation (OR=2.435). CONCLUSIONS: Although the prevalence of caries was slightly below the national mean, polarization of the disease was clearly observed. Education and no access to the dentist led to protection against the disease. These results may contribute to planning of oral health actions directed towards this target population for the control of caries.

Resumo em Inglês:

AIM: To investigate whether oral motor performance is determinant for the hydration status and the effect of a supplemental oral fluid supply on salivary osmolality. METHODS: The sample consisted of 99 children with cerebral palsy aged 6 to 13 years old. In this study, children participated in 2-day evaluations: 1st day - baseline: saliva collection, caries experience and oral motor performance evaluations; and 2nd day: saliva collection after supplemental fluid supply. Prior to each evaluation, the participants were trained for saliva collection. Unstimulated whole saliva was collected using cotton roll at baseline, with the amount of fluid usually offered by caregivers, and 48 h after baseline, with as much as twice the normal daily fluid intake previously offered. Salivary osmolality was measured using a freezing point depression osmometer. Caries experience index for decayed, missed and filled teeth (DMFT) was evaluated. According to the Oral Motor Assessment Scale, the children were classified into subfunctional or functional groups. Chi-square, Student's t test and Pearson's correlation coefficient were used. RESULTS: The subfunctional group presented a higher percentage of quadriplegic children (p<0.001), with significantly higher values for caries experience (p<0.001) and salivary osmolality (p<0.001), which did not diminish when supplemental fluid supply was offered, compared with the functional group (p=0.001). CONCLUSIONS: The effectiveness of oral motor performance plays an important role in the hydration status of children with cerebral palsy and those with worse oral motor performance may be at higher risk of oral diseases.

Resumo em Inglês:

AIM: To determine indicators of prognosis for mechanical risks of amalgam and composite resin restorations in permanent teeth. METHODS: Thirty-nine adult patients with direct clinical, photographic, radiographic and model examinations. A total of 256 restorations were classified as "not satisfactory," with Bravo or Charlie values according to the modified Ryge /USPHS criteria. The total "n" was divided into Bravo and Charlie groups according to the value obtained in the "marginal adaptation" parameter. Each of the groups was sub-divided by the type of material (amalgam and composite resins) and the class: occlusal (O) and proximal (MOD). RESULTS : Comparing the Bravo and Charlie groups, the statistically significant indicators were: the mesiodistal dimension (p=0.037), the distal isthmus (p<0.05), the average of the isthmuses (p<0.05), the distal (p<0.05) cavity depth, and the average depth of the MOD (p<0.05) cavities. It was concluded that the type and the class of the restoration are not indicators for sampling. CONCLUSIONS: With regard to the design of the cavity preparation, the valid mechanical risk indicators include the mesiodistal dimension, the distal isthmus, the average of the isthmuses, the depth of the distal cavity and the average depth of the MOD cavities. A simple clinical assessment does not provide sufficient information to establish the indicators for mechanical failure risk of restorations.

Resumo em Inglês:

AIM: To investigate the electromyographic activity of masticatory muscles in women with myogenic or mixed TMD treated with ultrasound and ultrasound associated with stretching. METHODS: Sixteen women with myogenic or mixed TMD, according to the Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD), participated in the study. The patients were evaluated using surface electromyography (sEMG) of the masseter and anterior temporalis muscles, during maximum intercuspation, before and immediately after application of therapeutic resources. All patients were treated by ultrasound (US), ultrasound associated with stretching and placebo ultrasound, by turns, once a week with a one-week minimum interval between them. RESULTS: There was greater symmetry of the masseter muscle electrical activity after ultrasound associated with stretching (p=0.03). The electromyographic values for the maximum intercuspation as well as the symmetry of anterior temporal muscle (p=0.47, p=0.84, p=0.84) and anteroposterior coefficient (p=0.07, p=0.84, p=0.57) showed no statistically significant difference after the intervention, placebo, ultrasound and ultrasound with stretching. CONCLUSIONS: These results indicate that a single application of ultrasound and ultrasound associated with stretching were not able to modify the activity pattern of the masticatory muscles during maximum intercuspation, except the symmetry of the masseter muscle that increased with the last, in women with myogenic or mixed temporomandibular disorder.

Resumo em Inglês:

AIM : To evaluate the influence of finishing and polishing techniques on the surface roughness of two composite resins (CRs) subjected to bleaching procedure. METHODS : Forty-eight CR specimens were divided into six groups (n=8). For G1 to G3, a microhybrid CR (Opallis; FGM) was used, and G4 to G6, received a nanohybrid CR (Brilliant NewLine; Coltène/Whaledent). All specimens were subjected to bleaching procedure with 35% hydrogen peroxide (two 45-min applications, with a 5-day interval). The surface roughness of all specimens was evaluated before and after the bleaching and/or finishing/polishing (Ra parameter) by a roughness meter. After bleaching, the groups were subjected to finishing and polishing procedures: G2 and G5 - felt discs + diamond pastes; and G3 and G6 - silicon rubber tips. The control groups (G1 and G4) had no finishing or polishing treatment after bleaching. Data were analyzed by ANOVA and Tukey's post-test, and t test for paired samples (a=0.05). RESULTS : bleaching treatment increased Ra values for the nanohybrid CR specimens, but both finishing/polishing techniques were able to reduce these values; for the microhybrid specimens, only finishing/polishing with silicon rubber tips decreased the roughness values. CONCLUSIONS : For both microhybrid and nanohybrid CRs, the silicon rubber tips were effective to reduce the surface roughness after bleaching procedure.