Influence of adhesive strategy on clinical parameters in cervical restorations: A systematic review and meta-analysis.

OBJECTIVES: We aimed to answer the following PICO question: "Is the risk of postoperative sensitivity (POS), retention rates and marginal discoloration of composite restorations [CR] bonded with self-etch (SE) in non-carious cervical lesions (NCCLs) of adults equals to etch-and-rinse (ER) adhesives?". METHODS: A comprehensive search was performed in May 2016 in the MEDLINE, Scopus, Web of Science, LILACS, BBO and Cochrane Library and SIGLE, abstracts of IADR, unpublished and ongoing trials registries, dissertations and theses without restrictions. Only randomized clinical trials that compared composite resin restorations placed with self-etch and etch-and-rinse in NCCLs were included. After removal of duplicates and non-eligible articles, 50 articles from 42 studies (follow-ups of the same study were merged) remained for synthesis of the risk of bias (Cochrane Risk of bias tool). RESULTS: Thirteen studies were at "high" risk of bias, yielding 29 studies for meta-analysis. No difference on the POS after restoration placement (risk ratio [RR] 1.04; 95% CI 0.81 to 1.34) as well as in the retention rates for all follow-up periods was observed. The etch-and-rinse approach produced less marginal discoloration at 18 months to 2 years (RR 1.51; 95% CI 1.21 to 1.90) and at 4 to 5 years (RR 1.81; 95% CI 1.28 to 2.55) (p<0.0007). CONCLUSIONS: The adhesive strategy did not influence the POS and the retention rates of composite resin in NCCLs in any of the follow-up periods; but less marginal discoloration was found in etch-and-rinse adhesives. CLINICAL SIGNIFICANCE: Composite resin restorations placed with self-etch and etch-and-rinse adhesives produce restoration with the similar clinical service and POS, however using etch-and-rinse adhesives one can reduce marginal discoloration. PROSPERO registration number: CRD42015019533.