LAUSR

CLINICAL RELEVANCE Vital bleaching impairs the bonding of adhesive systems to enamel and dentin. Thus, restoration placement should be delayed for at least two weeks after completion of bleaching procedures. SUMMARY Objective: This systematic review evaluates the influence of vital bleaching on the bond strength of adhesive systems to enamel and dentin.Methods: This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). In vitro studies comparing the bond strength of bleached and unbleached enamel and dentin were searched at the electronic databases-PubMed/MEDLINE, Scopus, and Web of Science-with no limit on year or language. The studies were screened and had data extracted by two reviewers independently. Bond strength data were meta-analyzed using the inverse variance method and the random effect model (p≤0.05).Results: The electronic search provided 4941 eligible studies, and 52 were included in the systematic review and the meta-analysis. The global meta-analysis showed that bleaching impairs the bond strength of adhesive systems to enamel and dentin (p<0.001; mean difference [MD]: -0.96; confidence interval [CI]: -1.18 to -0.73), regardless of the bleaching agent (p<0.001; MD: -9.98; CI: -1.37 to -0.58) or substrate (p<0.001; MD: -0.89; CI: -1.12 to -0.66). The detrimental effect of bleaching on bond strength was not observed after two and three weeks after bleaching (p=0.1; MD: -0.39; CI: -0.84 to 0.65; and p=0.18; MD: -0.99; CI: -2.45 to 0.47, respectively).Conclusion: This systematic review and meta-analysis demonstrated that vital bleaching impairs the bonding of adhesive systems to enamel and dentin, and this adverse effect persists for two weeks.