Temporomandibular disorder symptoms, sleep quality, and burnout syndrome in teachers.

OBJECTIVE: The aim of this study was to assess the association between the symptoms of temporomandibular disorder (TMD), sleep quality, and indicators of burnout syndrome in teachers. METHODS: This cross-sectional study included 330 teachers with an average age of 43 years. The Diagnostic Criteria for Temporomandibular Disorders, Pittsburgh Sleep Quality Index, and the questionnaire to assess burnout syndrome - teachers' version were used for data collection. Simple and multiple logistic regression models were applied to analyze the independent variables at a 5% significance level. RESULTS: Teachers with poor sleep quality, indicators of burnout syndrome, female sex, and impact on the domains of psychological exhaustion and guilt were, respectively, 1.91,1.92, 2.66, 1.97, and 2.60 times more likely to present at least one TMD symptom (p < 0.05). CONCLUSION: Teachers with indicators of burnout syndrome and impaired sleep quality were more likely to present with at least one TMD symptom.

Surface roughness of composite resins subjected to hydrochloric acid.

The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.