Three-year clinical effectiveness of a two-step self-etch adhesive in cervical lesions

A 3-yr randomized, controlled prospective study evaluated the clinical effectiveness of a mild two-step self-etch adhesive, Clearfil SE, in Class-V non-carious lesions. The hypothesis tested was that prior selective etching of enamel with phosphoric acid does not affect the 3-yr clinical performance of this adhesive. A total of 100 lesions in 29 patients were randomly restored in one or two pairs, according to two experimental protocols: (i) application of Clearfil SE according to the instructions of the manufacturer (C-SE non-etch); and (ii) similar application of Clearfil SE with prior etching of enamel cavity margins with phosphoric acid (C-SE etch). Clearfil AP-X was used as a restorative material. At 3 yr, 90% of the restorations were examined for retention, marginal integrity, marginal discoloration, caries recurrence, postoperative sensitivity, and preservation of tooth vitality. An excellent retention rate (100%) was noted after 3 yr of clinical functioning. Only one restoration of the C-SE etch group was clinically unacceptable owing to the presence of a severe cervical marginal defect. A pairwise comparison between both groups showed a significant difference only in the number of small marginal defects at the enamel side, which was higher in the C-SE non-etch group. These incisal defects were small and clinically irrelevant. Superficial marginal discoloration increased slightly in the C-SE non-etch group and was related to the higher frequency of small incisal marginal defects. In this latter group, localized marginal discoloration was observed significantly more in smokers. In conclusion, the clinical performance of the mild two-step self-etch adhesive, Clearfil SE, remained excellent after 3 yr of clinical functioning. Additional etching of the enamel cavity margins was not critical for its clinical performance.