RESUMO
BACKGROUND: This study aimed to evaluate the effects of an experimental bleaching gel made with TiO2 and chitosan, along with the Opalescence Boost PF and Philips Zoom bleaching agents, on tooth surface roughness, microhardness and colour. MATERIALS AND METHODS: The experimental gel, containing 6% hydrogen peroxide (HP), was evaluated against the two existing treatments, which incorporate 40% and 25% HP. For colour evaluation, 36 human premolar teeth were divided into three groups (n = 12). For surface roughness and microhardness evaluation, 72 bovine incisor samples were divided into six groups (n = 12). Data on colour alteration were analysed with the CIEDE2000 formula. Surface roughness was measured using a profilometer, and microhardness was measured with a Vickers hardness tester. ANOVA was used for statistical analysis. RESULTS: There were no statistically significant differences among the groups for surface roughness, microhardness values or colour change after bleaching (P > 0.05). The lowest bleaching efficacy was observed for the 40% HP agent, and the highest efficacy was observed for the 25% HP agent (P < 0.05). CONCLUSIONS: An experimental 6% HP gel containing TiO2 and chitosan provided effective bleaching without adverse effects on tooth surface roughness or microhardness. The use of TiO2 with chitosan can provide clinicians with positive results.
