Light-curing modes might interfere with staining susceptibility, stain's retention, and DC of a composite resin, compromising the clinical performance. The highest pigment absorption was not associated with the highest superficial staining of the composite resin. Alcoholic drinks lead to greater superficial staining and non-alcoholic solutions lead to a higher pigment concentration.

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Objective: To test the null hypothesis that there is no difference in mandibular growth between growing rats with posterior functional mandibular displacement and growing rats without functional mandibular displacement. Materials and Methods: Twenty female Wistar rats (5 weeks old) were randomized into two groups: (1) control and (2) mandible posterior displacement in the occluded condition induced by an occlusal guiding appliance. After 8 weeks all animals were sacrificed, cone beam computed tomography scan images of the heads were taken using the classic I-CAT, and acrylic rapidprototyped templates of the mandibles were constructed. Mandibular length, ramus height, and intercondylar distance were measured. Mandibular length and ramus height were submitted to the two-way analysis of variance, while intercondylar distance was analyzed by nonpaired Student's t-test. Results: Mandibular length was bigger (P , .0001) in the control than in the experimental group, but no significant difference was found between the left and right sides (P 5 .9380). No significant differences were observed for ramus height and intercondylar distance. Conclusions:The results of this study demonstrated that functional posterior displacement of the mandible in growing rats resulted in shorter mandibular length. (Angle Orthod. 2012;82:3-7.)

Relations between the mandibular canal and I, II and III Angle Classes in panoramic radiographs. Int. J. Morphol., 32(2):449-454, 2014. SUMMARY:To prevent injury to the inferior alveolar nerve during dental procedures, knowledge of its anatomical location and course of the mandibular canal is imperative. The aim of this study was evaluate the location on panoramic radiographs of the mandibular canal in relation to the apices of the permanent mandibular molars and base mandible, and relate the type of mandibular canal with Angle classes I, II and III. We evaluated 748 panoramic radiographs distributed according to sex and occlusal class (Angle I, II and III) of fully dentate individuals, 18-51 age group. The radiographs were divided according to Angle classes based on cephalometric tracing, clinical data from the medical records of each individual and the analysis of of the maxillar and mandibular dental arches models. The same individuals had the mandibular canal bilaterally assessed, and classified according to their location relative to the root apices of the mandibular molars and mandible base. Measurements of the distance from the mandibular canal to the apices of the teeth and mandible base were made on the Software ImageLab2000®. The intra-observer reproducibility of measurements on radiographs was assessed using the coefficient of variation (p<0.0001). Data were submitted to Kruskal-Wallis test, on software BioEstat 5.0. There were statistically significant differences (Kruskal-Wallis test, p <0.0001) between the occlusal classes, with the type of mandibular canal. A larger number of canals types 2 and 3 in class III individuals than in others. In conclusion, the location of the mandibular canal presents morphological changes in relation to the apices of the permanent molars, and the mandibular base according to the Angle classes I, II and III.

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Temporomandibular disorders (TMD) affecting the articular disc and/or the facial muscles are common among the population, recording a higher incidence in women age 20-40 years. The aim of this study was to investigate the correlation between facial types and muscle TMD in women. This study comprised 56 women age 18 to 49 years, seeking treatment for TMD at the School of Medicine, Federal University of São Paulo. All of the study individuals were diagnosed with muscle TMD, based on the Research Diagnostic Criteria (RDC). Facial type was determined using the Facial Brugsch Index and classified as euryprosopic (short and/or broad), mesoprosopic (average width) and leptoprosopic (long and/or narrow). The data were submitted to the Chi-square test and ANOVA-Tukey's test to conduct the statistical analysis. The faces of 27 individuals were classified as euryprosopic (48%), 18 as mesoprosopic (32%), and 11 as leptoprosopic (20%). A statistically significant difference (Chi-square, p = 0.032) was found among the facial types, in that leptoprosopic facial types showed the lowest values for muscle TMD. A greater number (p = 0.0007) of cases of muscle TMD were observed in the 20 to 39 year-old subjects than in the subjects of other age segments. In conclusion, women with euryprosopic facial types could be more susceptible to muscle TMD. Further studies are needed to investigate this hypothesis.

Purpose: The mandibular foramen, located on the internal surface of the mandibular ramus, is an important anatomical landmark for the success during the inferior alveolar nerve block. This cross-sectional retrospective study aimed to evaluate the location of the mandibular foramen through Cone-Beam Computed Tomography (CBCT) in different facial shapes. Materials and Methods: The determination of the location of the mandibular foramen was performed using CBCT of mesocephalic, dolichocephalic and brachycephalic patients (n=40 each). The ramus width (W), the distance from the mandibular foramen to the deepest point of the anterior border of the mandibular ramus (D), the distance from the mandibular foramen to the lowest point of the mandibular notch (V) and the distance from the inferior border of the mandible to the lowest point in of the mandibular border (R), as well as the ratios W/D and V/R, were measured. ANCOVA, two-way ANOVA and Chi-square tests were used to analyze the variation among the facial shapes. Results: The ramus width (W) was greater (p<0.0001) in the brachycephalic (28.4±0.5 mm) than in both mesocephalic (26.8±0.36 mm) and dolichocephalic (25.5±0.39 mm) patients. D (p=0.0433) and R (p=0.0072) were also greater in the brachycephalic (17.7±0.36 mm; 43.4±0.75 mm, respectively) than dolichocephalic (16.5±0.3 mm; 40.3±0.63 mm, respectively), but both did not differ from mesocephalic (17.3±0.36 mm; 41.8±0.66 mm, respectively) patients. The other measurements (V, W/D and R/V) did not significantly differ among facial shapes. Conclusion: The localization of the mandibular foramen was, in the horizontal direction, more posterior in the brachycephalic patients and, in the vertical direction, higher in the dolichocephalic patients, when compared to the other groups analyzed. Thus, the anatomic data found in this study may help dentists to increase the success of the inferior alveolar nerve block and prevent surgical complications.