The influence of violet LED application time on the esthetic efficacy and cytotoxicity of a 35% H2O2 bleaching gel

Author(s)

Ribeiro, Rafael Antonio de Oliveira ; Peruchi, Victoria ; Fernandes, Lidia de Oliveira ; Anselmi, Caroline ; Soares, Igor Paulino Mendes ; Hebling, Josimeri ; Costa, Carlos Alberto de Souza

• Document type: Journal article
• Source: Photodiagnosis and Photodynamic Therapy; v. 40, p. 6-pg., 2022-12-01.

Abstract

Objective: To assess the potential influence of violet LED (V-LED) application time on the esthetic efficacy and cytotoxicity of a 35% H2O2 bleaching gel.Methodology: Stained and standardized enamel/dentin discs were subjected to one in-office tooth bleaching session (45 min), and the gel was either irradiated or not with V-LED. Thus, the following groups were estab-lished (n = 8): G1: No treatment (negative control, NC); G2: 35% H2O2 (positive control, PC); G3: 35%H2O2 + V- LED/15 min; G4: 35%H2O2 +V-LED/30 min; G5: 35%H2O2 +V-LED/45 min. First, esthetic efficacy was assessed (Delta E00 and Delta WI). Discs assembled in artificial pulp chambers were subjected to the same bleaching treatments. Then, the extracts (culture medium + diffused bleaching gel components) were collected and applied to MDPC-23 pulp cells, which were analyzed for viability (Live/Dead, MTT) and oxidative stress (OxS). The amount of H2O2 in the extracts was also determined (leuco crystal-violet/peroxidase). The data were subjected to ANOVA/Tukey at a 5% significance level.Results: Although esthetic efficacy did not differ among the irradiated groups (G3, G4, and G5) (p > 0.05), their results were higher than in G2 (PC; p < 0.05). In the irradiated groups, the cell viability and OxS as well as the amount of H2O2 in the extracts were statistically similar to G2 (PC), regardless of irradiation time (p > 0.05).Conclusion: Although V-LED improves the esthetic outcome of in-office tooth bleaching, increasing irradiation time does not effect the color changes and cytotoxicity of this professional therapy. (AU)

• FAPESP's process: 20/09095-8 - Development of an innovative strategy for in-office tooth bleaching: aesthetic effectivity and biocompatibility associated with reduced clinical time
• Grantee: Carlos Alberto de Souza Costa
• Support Opportunities: Regular Research Grants