Effect of an Experimental Ozone-based Desensitizing Gel on Tooth Sensitivity and In-office Dental Bleaching

Aims: This study evaluated bleaching efficacy (BE), tooth sensitivity (TS), and enamel microstructure after in-office dental bleaching treatment with experimental desensitizing gel containing ozone (O3). Study Design: For the TS and BE analysis, forty third molars were divided into two groups (n=20): OF-B, ozone-free desensitizer and bleaching agent; O-B, 16 ppm ozonized desensitizer and bleaching agent. Place and Duration of Study: Dental Clinic of the State Western University of Parana, between June 2019 and April 2020. Methodology: The calculation indicated that 20 teeth per group, totalizing 40 teeth (30 patients), would be sufficient to detect significant differences in TS and BE (power of 80%, significance level of 5%). Dental bleaching was performed with 35% hydrogen peroxide. TS was assessed using a visual analog scale, and BE was assessed using the Vitapan Classical color visual scale. After tooth extraction, the enamel microstructure was evaluated by micromorphological analysis using a scanning electron microscope (SEM). For this analysis, eighty third molars were used, divided into four groups (n=20): OF-B and O-B previously described; OF-WB, ozone-free desensitizer without bleaching agent; O-WB, ozonated desensitizer 16 ppm without bleaching agent. Statistical analyzes of all variables were performed with a significance level of α = 0.05. The Mann-Whitney test was used for intergroup analysis for two outcomes, and the Friedman test was used for intragroup analysis. McNemar's exact test compared the risks of tooth sensitivity in the two groups (α = 0.05). Results: TS was higher in the OF-B group. No significant differences were observed in BE. No modification was demonstrated in the enamel microstructure by the action of O3. Conclusion: The experimental gel containing O3 is a promising desensitizing agent for clinical use, reducing tooth sensitivity, without interfering with the color achieved by dental bleaching and in the microstructure of tooth enamel.