Effects of a 0.5% Experimental Propolis Gel on Tooth Sensitivity Control and Post-bleaching Color Change: a Randomized Clinical Trial

This randomized, parallel, double-blind, placebo-controlled clinical study aims to investigate the effects of an experimental 0.5% propolis gel on controlling tooth sensitivity and discoloration after in-office dental bleaching. Sixty-six volunteers will be selected according to inclusion and exclusion criteria and will be randomly assigned to three experimental groups: Placebo - received application of a gel without active ingredient (K-Y Original), KF2 - received application of 5% potassium nitrate and 2% sodium fluoride (Desensitize KF 2%), and Propolis 0.5% - application of the experimental 0.5% propolis gel. All participants will undergo two in-office bleaching sessions with 35% hydrogen peroxide, with seven-day intervals between them. The bleaching agent will be applied for 30 minutes. The desensitizing agents will be applied prior to bleaching and kept in contact with the vestibular dental surface for ten minutes. Sensitivity will be monitored daily using the Visual Analogue Scale for fourteen days, while color change will be determined by spectrophotometry, using the parameters of the CIELab* system and calculation of ΔE00, measured before bleaching (T0) and 7 days after the second bleaching session (T1). The data will be subjected to statistical analysis according to sample distribution, adopting a power of 80% and a significance level of 5%.