Method: 133 cylindrical specimens from bovine teeth with 3 mm in diameter and with 1 mm enamel and 1mm dentin thick were divided in groups, according to bleaching treatment: negative control (non-bleached), bleached with 10% carbamide peroxide (CP); bleached with 7.5% hydrogen peroxide (HP) and bleached with 35% hydrogen peroxide. 10% CP gel was applied for 8 h/day and 7.5% HP for 1 h/day, during 14 days. For 35% HP treatment, two sessions of 45 min each were performed. In intermediate periods specimens were stored in artificial saliva. Experimental bleached groups were subdivided according to the simulation of pulpal pressure (34 cm H2O) during bleaching treatment. Initial color measurement and after bleaching treatment were assessed by spectrophotometry, using CIE L*a*b* system.
Result: The application of ANOVA (5%) revealed no significant difference for total color variation (ΔE) among experimental bleached groups. There was significant difference of ΔE means for all experimental groups compared to negative control group, according to Dunnett’s test (p<0.0001).
Conclusion: It was concluded that all bleaching gels tested showed bleaching efficacy compared to non-bleached group and that the simulated pulpal pressure did not influence the bleaching outcomes of the tested gels.
Keywords: Bleach, Dentin and Enamel
See more of: Dental Materials 11: Color and Appearance (Esthetics)