Effect of the reduction in the exposure time to at-home bleaching gel on color change and tooth sensitivity: A systematic review and meta-analysis

Abstract

Objective: To investigate the effect of reducing exposure time to at-home bleaching gel on color change and tooth sensitivity.

Materials and methods: The search was carried out using PubMed, Scopus, Web of Science, EMBASE, LILACS, Cochrane. Randomized clinical trials (RCTs) were included involving adult patients who have never undergone bleaching treatment before (P), subjected to bleaching with a reduced exposure time to the at-home bleaching agent (I) compared to those who used it for the time indicated by the manufacturer (C), to evaluate the effects on color change and tooth sensitivity (O). The Cochrane guidelines for the Risk of Bias Assessment Tool (RoB 2.0) and GRADE were used to assess risk of bias and quality of evidence, respectively.

Results: Using at-home bleaching gel for the period recommended by the manufacturer resulted in significantly higher ΔE_ab and ΔWI_D values and better subjective color change (ΔSGU-Classical), regardless of the evaluation time. Regarding the post-bleaching evaluation, no significant differences were found for ΔE₀₀ immediately after bleaching or ΔSGU (Bleached) at any time. Reducing the time of use significantly decreased tooth sensitivity events.

Conclusions: Reducing exposure time to at-home bleaching gel reduces tooth sensitivity events; however, most of the parameters that assess color change indicate using at-home bleaching gel for the time recommended by the manufacturer.

Clinical significance: Reducing exposure time to at-home bleaching gel should be applied with caution in clinical practice. Although the evidence suggests a reduction in tooth sensitivity events, bleaching effectiveness was significantly higher after using the bleaching gel for the time indicated by the manufacturer.

Keywords: Bleaching agents; Time; Tooth bleaching; Tooth sensitivity.