Comparison of the bond strength of composite resin to Er:YAG laser-irradiated enamel/dentin pre-treated with various methods

The purpose of this study was to compare the effects of pre-treatment on bond strength between composite resin and Er:YAG laser-irradiated enamel/dentin. The Er:YAG laser was irradiated on 60 extracted human teeth at following conditions; for enamel: 200 mJ/4 Hz, total energy 30 J, for dentin: 100 mJ, total energy 15 J. The irradiated 60 teeth were divided into six groups (n = 5); Gr.1: ground with silicon carbide paper; Gr.2: laser was irradiated at foregoing condition; Gr.3: 37% phosphoric acid was applied to irradiated surface; Gr:4: ultrasonic scaler was applied to irradiated surface; Gr5: air scaler was applied to irradiated surface; Gr.6; air-powder polisher applied to irradiated surface. SE bond and AP-X (Kuraray) were applied and cured. Tensile bond strengths (TBS) were measured after 24 h. The data were analyzed using ANOVA and Sheffe's-tests. TBS of dentin was significantly higher than that of enamel. Significant differences among Gr.1 and 2, 3, 4, 5, Gr.2 and 3,4,5,6, Gr.3 and 6, Gr.4 and 6, Gr.5 and 6 were observed. The application of air-powder polisher for Er:YAG laser-irradiated enamel/dentin was effective to obtain high TBS. (C) 2002 Elsevier Science B.V. All rights reserved.