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Objective: To compare the adhesive strength in dentin of three universal adhesive systems in vitro by means of the shear test. Materials and methods: Seventy-five bovine teeth were selected and cut. Dentin was exposed from the buccal surface of the crowns with 220 grit sandpaper, and samples were then inserted in transparent acrylic bases (15x10mm). The samples were randomly divided in 3 groups (n=25): G1-Universal adhesive system Scotchbond™ Universal (3M ESPE-USA); G2-Universal adhesive system Peak Universal Bond (Ultradent); G3-Universal adhesive system Tetric N-Bond (Ivoclar Vivadent). The adhesive procedures were carried out according to the instructions of each manufacturer and the restorative procedures were carried out with micro-cylinders (made of Tygon type tubing 0.79x1.5mm) of the composite resin Filtek™ Z350XT-A2 (3M ESPE-USA). The samples were incubated at 37ºC (+/-5ºC) for 24 hours. Adhesive strength was evaluated in a universal test machine by means of the shear test (0.5mm/ min, 500N) and the resulting fracture type was evaluated with a Dinolite digital microscope (x200). The results were analyzed by descriptive statistics (Mean±SD), and inferential statistics by a one-way ANOVA. Results: No statistically significant differences were found between the universal adhesive systems evaluated G1 (14.91±4.76), G2 (16.90±4.11) and G3 (17.34±4.04)/(p=0.114). Conclusions: The shear test resulted in similar values of immediate adhesive strength of the three universal adhesive systems used., Revisión por pares

Objective: To compare condylar dimensions of young adults with Class II and Class III skeletal patterns using cone-beam computed tomography (CBCT). Materials and methods: 124 CBCTs from 18-30 year-old patients, divided into 2 groups according to skeletal patterns (Class II and Class III) were evaluated. Skeletal patterns were classified by measuring the ANB angle of each patient. The anteroposterior diameter (A and P) of the right and left mandibular condyle was assessed from a sagittal view by a line drawn from point A (anterior) to P (posterior). The coronal plane allowed the evaluation of the medio-lateral diameter by drawing a line from point M (medium) to L (lateral); all distances were measured in mm. Results: In Class II the A-P diameter was 9.06±1.33 and 8.86±1.56 for the right and left condyles respectively, in Class III these values were 8.71±1.2 and 8.84±1.42. In Class II the M-L diameter was 17.94±2.68 and 17.67±2.44 for the right and left condyles respectively, in Class III these values were 19.16±2.75 and 19.16±2.54. Conclusion: Class III M-L dimensions showed higher values than Class II, whereas these differences were minimal in A-P., Revisión por pares