Microleakage study of three adhesive systems.

The purpose of this in vitro study was to evaluate the efficacy of three hydrophilic dentin adhesive systems to reduce class II restoration microleakage. A total of 60 human molar teeth were used in which two box cavities were made on the distal and mesial surfaces, with a cervical margin in dentin. These cavities were randomly divided into 3 groups (n = 40 each), according to adhesive system tested: G1: OptiBond SOLO; G2: Amalgambond Plus; G3: Etch & Prime 3.0. The cavities were restored with the composite resin Z-100. The groups were thermocycled 2000 times (5 +/- 1 degrees C and 55 +/- 1 degrees C) with a dwell time of 1 min. The teeth were then immersed in 2% methylene blue, pH 7.0, for 4 h, sectioned and observed with a stereomicroscope MEIJI 2000 (35X). The evaluation was made using scores (0-4) and the results were expressed through the sum of the ranks. G1 = 1994.00; G2 = 2294.00; G3 = 2972.00. The three groups were significantly different. The self-etching adhesive system Etch & Prime 3.0 was less effective in preventing microleakage. The OptiBond SOLO adhesive was the most effective in reducing microleakage in dentin margins when compared with Amalgambond Plus and Etch & Prime 3.0.