Two-year clinical evaluation of self-etching adhesives in posterior restorations

To evaluate the 2-year clinical performance of three self-etching adhesives and one etch-and-rinse adhesive (control) in posterior composite restorations.

Upon approval by the Institutional Review Board, 121 restorations were inserted in 38 subjects. The adhesives were applied as per manufacturers' instructions. Preparations were restored with a nanofilled composite resin (Filtek Supreme, 3M ESPE) and evaluated at baseline, 6 months, 1 year, and 2 years. Statistical analyses included the McNemar and the Mann-Whitney non-parametric tests (p < 0.05).

At 2 years, 91 out of 121 restorations were evaluated using the USPHS modified criteria. The number of alpha ratings decreased significantly from baseline to 2 years for Adper Prompt L-Pop, Clearfil S3 Bond, and iBond in the categories color match, marginal staining, and marginal adaptation. For One-Step Plus, only marginal staining was significantly worse at 2 years than at baseline. Postoperative sensitivity to air improved significantly for One-Step Plus at 2 years, but this improvement was already detected at 1 year. When the 2-year evaluation criteria were pooled by pairs of adhesives, One-Step Plus resulted in a significantly greater number of alfa ratings for marginal adaptation than the other three adhesives. On the other hand, iBond resulted in a significantly lower number of alfa ratings than any of the other 3 adhesives for color match and marginal staining. Adper Prompt L-Pop, Clearfil S3 Bond, and One-Step Plus resulted in a statistically similar number of alfa ratings for marginal staining and color match. There were no significant differences in any of the evaluation criteria between Clearfil S3 Bond and Adper Prompt L-Pop.

Only One-Step Plus, the etch-and-rinse adhesive, resulted in good marginal adaptation at 2 years. One of the self-etching adhesives, iBond, resulted in unacceptable clinical performance.