Using violet light during in-office tooth bleaching to enhance the efficacy of carbamide peroxide without increasing...

This systematic review and meta-analysis evaluated whether irradiating carbamide peroxide (CP) with violet light can enhance the effect of in-office tooth bleaching without increasing sensitivity. Searches were conducted in PubMed, Embase, Scopus, Web of Science, and Google Scholar databases. Randomized clinical trials (RCTs) that performed in-office tooth bleaching with CP irradiated with violet light or not were included in all languages ​​and years of publication. The systematic steps followed the PRISMA protocol. The risk of bias was assessed by the RoB 2 tool. The GRADE was used to analyze the certainty of evidence. Meta-analysis was conducted with RevMan 5.4 software to evaluate tooth color change (CC) and bleaching sensitivity (BS). The CC was assessed by mean difference (MD) and the BS by risk difference (RD). Three RCTs were included in this systematic review. A statistically significant difference for CC favoring the application of violet light associated with the CP (MD, 3.35; 95% CI, 0.80, 5.89) was obtained, while no difference was found for BS (RD, 0.09; 95% CI, -0.03, 0.21). Violet light irradiation improved carbamide peroxide's in-office tooth bleaching effect without increasing sensitivity. However, the results should be interpreted with caution due to the moderate certainty of the evidence.