Evaluation of Serum Oxidative Stress Biomarker Alterations Following Tooth Bleaching with 21% Carbamide Peroxide

Abstract

Background: One of the common methods for teeth whitening is home bleaching (HB), which uses oxidizing agents such as carbamide peroxide (CPO) and hydrogen peroxide (H2O2). These oxidizing compounds may disrupt the oxidant-antioxidant balance, leading to oxidative stress that can damage cells. Oxidative stress has been linked to various health issues, including cancer, cardiovascular diseases, diabetes, neurological disorders, aging, and more. Objectives: The aim of this study was to compare the serum levels of oxidative stress factors before and after using 21% CPO. Methods: This semi-experimental study included 19 patients who requested teeth whitening. A custom tray was fabricated for both jaws after taking the jaw impression. Patients were given 21% CPO gel (Opalescence PF, Ultradent, USA) to use for 6 hours nightly over 24 days. Blood samples (9 cc) were collected from participants once before the study and once after the whitening period. To assess serum levels of oxidant and antioxidant factors and their balance, malondialdehyde (MDA) and total antioxidant capacity (TAC) tests were performed. Data were analyzed using SPSS software (version 27) with a confidence interval (CI) of 95% and a paired t-test. Results: Only 22 participants completed the study. Post-whitening MDA and TAC levels were not significantly higher than baseline values (P = 0.824 for MDA, P = 0.918 for TAC). Conclusions: The findings of this study suggest that HB with 21% CPO does not significantly increase oxidative stress levels in serum.