White Diet Is Not Necessary During Bleaching Treatment

OBJECTIVES

This study aimed to conduct a systematic review with network meta-analysis (NMA) to answer whether the following of a white diet is necessary during dental bleaching and if there is any coloring food that would impact more significantly the bleaching efficacy.

DATA SOURCES

The review followed the PRISMA Extension Statement for network meta-analysis. Six electronic databases (PubMed, Scopus, Web of Science, Embase, LILACS, and SciELO) were systematically searched from the beginning of documentation to April 15, 2024, and the gray literature was also assessed using the Google Scholar platform.

STUDY SELECTION

The eligibility criteria considered clinical trials comparing the bleaching efficacy of treatment using peroxide agents in participants that followed a white diet (i.e., a diet with restriction of coloring food and beverages; control group) and those who had either a supplemented intake of pigments or an unrestricted diet (intervention group). The risk of bias was assessed using RoB2 (for randomized clinical trials/RCT) and ROBINS-I (for non-randomized clinical trials/NRCT) tools, and the quality of evidence was checked using the GRADE tool. The color change data of groups were compared using both standard pairwise meta-analysis (SPMA) and Bayesian NMA.

RESULTS

The search resulted in 1051 studies, of which seven were included in the review. Four studies had RCT design, whereas the other three studies were NRCTs. Different bleaching regimens and peroxide agents were investigated, and all studies evaluated the color change obtained before (baseline) and after bleaching treatment using a digital spectrophotometer (Vita Easyshade) according to the CIELab color system. All seven studies were classified as having low risk of bias. Concerning the SPMA, there was no difference between the intervention and control groups regardless of the bleaching technique (p=0.15), the type of peroxide and concentration of the gel (p=0.38), and the period of bleaching treatment (p=0.20). Regarding the NMA, the white diet group showed similar color change values than the groups that received pigment supplementation with grape juice, coffee, tea, wine, cola, or an unrestricted diet (p>0.05). According to the probabilistic analysis, the unrestricted diet group ranked better than the other groups at the first and second weeks of treatment, and at the third week of treatment, all groups performed similarly in terms of bleaching efficacy, except for the group supplemented with coffee, which ranked worst. The GRADE analysis revealed a moderate quality of evidence for the RCT and NRCT studies included in the review.

CONCLUSIONS

The consumption of cola-based soft drink, coffee, black tea, grape juice, and red wine, as well as the following of a totally unrestricted diet, do not have a significant influence on the effectiveness of bleaching as compared to a white diet regimen during the course of the treatment.

CLINICAL SIGNIFICANCE

The accumulated evidence indicates that restricting the intake of dietary pigments during dental bleaching treatment is not essential. When comparing the effects of various staining beverages on the efficacy of dental bleaching, no significant differences were observed in the color change obtained whether coloring food/beverages were restricted or not to the participants.