Purpose: The aim of this study was to evaluate the clinical retention to dentin of a single-step self-etching adhesive system. Materials and Methods: A total of 133 Class V restorations were placed with the self-etching primer Xeno III and a resin composite (Tetric Ceram) or a polyacid-modified resin composite (Dyract AP) in noncarious cervical lesions without intentional enamel involvement. The restorations were evaluated at baseline and then every 6 months during a 2- year follow-up. Dentin bonding efficacy was determined by the percentage of lost restorations. Results: During the 2 years, 130 restorations could be evaluated. The cumulative loss rate at 2 years was 7.7%, with no significant differences between the two restorative materials. The self-etching adhesive fulfilled the 18-month full acceptance ADA criteria. Conclusion: The single-step self-etching adhesive showed acceptable clinical retention rates to dentin surfaces during the evaluation period independent of restorative material used. Keywords: adhesion, clinical, cervical, dental material, etch, resin, restoration, self-etching