摘要：OBJECTIVE: Er:YAG laser can be used instead of air-turbine for cavity preparation in dentistry. However, the bond strength achieved after Er:YAG preparation is not as good as that achieved after bur preparation. In this study the effect of Nd:YAG laser treatment on the adhesive applied onto Er:YAG-prepared coronal dentin was investigated. Bond strength achieved in this fashion was compared with that achieved after bur preparation. MATERIALS AND METHOD : Coronal dentin was prepared either with tungsten carbide bur or with Er:YAG laser. Then, adhesive (Scotchbond Multi-Purpose, Adper Single Bond 2, Clearfil SE and Clearfil S3) was applied onto the dentin. In some of the Er:YAG-prepared teeth, the adhesive was treated with Nd:YAG laser (100 mJ, 10Hz) prior to polymerization. The bond strength was evaluated using the microtensile test. RESULTS: The bur group, as expected, revealed greater bond strength. Nd:YAG treatment increased the bond strength in all adhesive systems. Although bond strength values were still lower in the Nd:YAG-treated group, no statistically significant difference was found between the Nd:YAG-treated and bur groups (p>0.05). SEM analysis showed that coronal dentinal tubule penetration was greater when the adhesive was treated with Nd:YAG laser prior to polymerization. CONCLUSION: Treatment of the adhesives with the Nd:YAG laser was found to improve the adhesive bond strength at the coronal dentin.
