Efficacy of Chitosan in Reducing Tooth Sensitivity Induced by in-Office Bleaching: A Randomized, Double-blind, Controlled Clinical Trial

Aims: To evaluate the effect of incorporating chitosan microparticles into a commercial desensitizing agent on tooth sensitivity during and after in-office bleaching procedures. Study Design: Randomized, controlled, double-blind clinical trial. Place and Duration of Study: Department of Restorative Dentistry of State University of West Paraná (UNIOESTE), between June and December 2017. Methodology: Forty-two patients were selected and randomly assigned to two groups (n = 21 each). The DKF group received only a commercial desensitizing agent, while the DKF + CHI group received the same agent combined with chitosan microparticles. In both groups, 35% hydrogen peroxide was used for in-office bleaching on the upper arch. The desensitizing gel was applied for 10 minutes prior to bleaching. Tooth sensitivity was self-reported by patients using a visual analog scale at 5-minute intervals during bleaching (up to 45 minutes) and at 1, 24, and 48 hours post-procedure. Color change was evaluated at baseline and after 7 days. The Mann–Whitney U test was used for statistical analysis (P < 0.05). Results: The DKF + CHI group reported significantly lower sensitivity levels than the DKF group at 35, 40, and 45 minutes during the procedure, and at 60 minutes post-treatment (p < 0.05). The probability of pain occurrence was markedly reduced in the group treated with chitosan, supporting its potential effectiveness as a desensitizing adjunct in clinical bleaching protocols. No statistically significant differences were observed between the groups regarding bleaching effectiveness. Conclusion: The incorporation of chitosan microparticles into the desensitizing agent effectively reduces tooth sensitivity associated with in-office bleaching procedures, without compromising the bleaching outcome.