Objectives: Different surface treatments may affect bonding performance of adhesive systems to dentin. This study evaluated the influence of different methods of surface treatment on adhesion of bonding agents to dentin.
Methods: Dentin surfaces abraded with #600-grit SiC paper were used as control. Three methods of surface treatment (sono-abrasion, air-abrasion and Er:YAG laser irradiation) were used under specific parameters. Four adhesive systems (Tyrian, Clearfil SE Bond, Unifil Bond and Single Bond) were applied to treated surfaces, according to the manufacturers' instructions. Composite blocks were built on bonded surfaces, then restored teeth were vertically and serially sectioned to obtain bonded slices for interfacial micromorphologic analysis or to produce beam specimens for mu-TBS bond test. Data were analyzed with two-way ANOVA and Tukey test at a significance level of 5%.
Results: The results indicated that the preparation of dentin with sono-abrasion or laser did not affect the bond strength, while the preparation of dentin with SiC paper and air-abrasion influenced the bond strength for some systems. A clear difference of the preparation of dentin surfaces and formation of hybrid layer and resin tags were noted.
Conclusion: Bonding effectiveness of both the etch-and-rinse and the self-etch adhesives can be influenced by different methods of dentin preparation.
Keywords: Adhesive systems; Air-abrasion; Bond strength; Dentin; Er: YAG laser; Sono-abrasion.