Peroxide-Free Titanium Dioxide Nanoparticle-Based Photocatalytic Bleaching: In Vitro Study on Bovine Teeth.

Objective

This study is aimed at assessing the bleaching efficacy of titanium dioxide (TiO2) nanoparticle suspensions at different concentrations and exposure times for photocatalysis and evaluating their potential as a peroxide-free alternative to carbamide peroxide in dental bleaching. Materials and

Methods

Sixty bovine incisors were stained with black tea and treated with different bleaching protocols: (1) control (16% carbamide peroxide), (2) TiO2-50 wt% for 10 min (TiO2 50/10), (3) TiO2-50 wt% for 50 min (TiO2 50/50), (4) TiO2-10 wt% for 50 min (TiO2 10/50), and (5) TiO2-10 wt% for 10 min (TiO2 10/10). The agents were exposed to UV light (395 nm) for photocatalysis before application. All treatments were applied daily for 2 h over 21 days. Color change (ΔE00) was measured using a digital spectrophotometer (VITA Easyshade V), and pH was assessed using pH strips.

Results

The data were analyzed using one-way ANOVA and Tukey's test. TiO2 50/50 showed significantly superior bleaching effects compared to all other groups (p < 0.001). TiO2 10/50 and TiO2 10/10 demonstrated intermediate bleaching results, with no significant difference between them (p = 0.0875). The control and TiO2 50/10 groups exhibited the lowest color variation (p = 0.102). All groups maintained a pH of 6 before and after 2 h of the at-home bleaching protocol.

Conclusion

TiO2 nanoparticle suspensions may be a viable peroxide-free alternative for dental bleaching, particularly at higher concentrations and longer photocatalysis exposure times.