Effect of low-level laser therapy in tooth bleaching sensitivity:

Aim: Tooth sensitivity is the principal side effect as a clinical consequence resulting from tooth bleaching. Therefore, several strategies have been proposed to control this adverse effect. The present study aimed to investigate the effect of low-level laser therapy on tooth bleaching sensitivity compared to the placebo group or no intervention group.  Literature Review: A search was carried out in six databases (BVS, PubMed, Scopus, Web of Science, Scielo, Cochrane library) until April 2024. Only studies with a randomized clinical trial or split-mouth design that performed in-office tooth bleaching and evaluated the effect of low-level laser therapy on post-bleaching sensitivity were included. The search was not limited by language or time. Due to the great heterogeneity observed between studies, the data were analyzed qualitatively. Results: Of the 586 records found, 478 remained after removing duplicates. Thus, 21 articles were accessed in full and only ten met the eligibility criteria and were included in the present review. Most of the studies (n=6; 60%) were with split-mouth designs. Considering the ten studies included in the present review, only two studies did not find a significant reduction in sensitivity after tooth bleaching in at least one of the periods evaluated. The application of low-level laser therapy before or after in-office tooth bleaching does not seem to influence the results. Conclusion: we observed that low-level laser therapy appears to have a positive effect in preventing sensitivity after tooth bleaching. This effect seems to only be significant in the first few days after tooth bleaching.