CYTOTOXIC EFFECTS OF WHITENING AGENTS ON PERIODONTAL TISSUES

Abstract

Dental bleaching is a widely used, conservative aesthetic procedure; however, its safety depends on the agent's concentration, exposure time, the technique employed, and the patient's clinical condition. This study aimed to analyze the main biological and cytotoxic effects associated with hydrogen peroxide and carbamide peroxide-based agents found in the literature, focusing on tooth sensitivity, gingival irritation, enamel alterations, and impacts on pulp cells and fibroblasts. A literature review was conducted based on ten studies—including literature reviews, systematic reviews, *in vitro* studies, and clinical trials published between 2015 and 2026. The studies were examined regarding the bleaching agent, concentration, application time, experimental model, and primary outcomes. Results indicated that adverse effects are primarily influenced by concentration and contact time, with tooth sensitivity and gingival irritation being the most frequent clinical manifestations. Experimental studies also demonstrated reduced cell viability and physical alterations to the enamel under certain conditions. It is concluded that dental bleaching can offer a good safety profile when tailored to the individual and supervised, requiring careful protocol selection and control of factors associated with adverse effects.