Estudo clínico randomizado de diferentes adesivos autocondicionantes. Análise da resistência de união

Abstract

Purpose: Evaluate the bond strength to dentin of three different bonding system (conventional 3 steps, two steps and universal self-etching) after 1 week and 6 months in oral environment. Methods: Class I cavities were prepared in third molars of 30 patients, that were randomly divided into 3 groups according to the adhesive system used, Scotchbond Multipurpose (SM), Clearfil Protect Bond (CF) and Scotchbond Universal (UN) and subdivided in two groups according to the length of stay in the oral environment, 1 week (1S) and 6 months (6M). After standing in the oral environment, teeth were extracted, cut into sticks and subjected to microtensile test. Data were submitted to Shapiro-Wilk test and ANOVA (two-way), followed by Tukey post hoc, significance level of 5 % and the fracture pattern analyzed. Results: Average values (MPa ± SD) of the groups were SM-1S: 39.50 ± 7.92; 6M-MS: 29.68 ± 1.82; CF-1S: 30.48 ± 1.44 CF-6M: 28.59 ± 4.13; UN-1S: 30.62 ± 3.24; UN-6M: 26.71 ± 2.05. There was significant difference for both, the adhesive system factor and the time factor. The SM -1S group showed resistance values significantly higher than the other groups, with no differences between them. The fracture analysis showed predominance of mixed fracture for group 1 and adhesive fracture to the other groups. Clinical Significance; The findings of this study indicate that the studied adhesive systems presented similar bond strength after 6 months in the oral environment