Enhanced tooth bleaching with a hydrogen peroxide/titanium dioxide gel.

ABSTRACT

BACKGROUND: This study aimed to explore the effects of the titanium dioxide (TiO2) concentration and particle size in hydrogen peroxide (HP) on tooth bleaching effectiveness and enamel surface properties. METHODS: TiO2 at different concentrations and particle sizes was incorporated into 40% HP gel to form an HP/TiO2 gel. The specimens were randomly divided into 8 groups C1P20 HP + 1% TiO2 (20 nm); C3P20 HP + 3% TiO2 (20 nm); C5P20 HP + 5% TiO2 (20 nm); C1P100 HP + 1% TiO2 (100 nm); C3P100 HP + 3% TiO2 (100 nm); C5P100 HP + 5% TiO2 (100 nm); C0 HP with LED; and C0-woL HP without LED. Bleaching was conducted over 2 sessions, each lasting 40 min with a 7-day interval. The color differences (ΔE00), whiteness index for dentistry (WID), surface microhardness, roughness, microstructure, and composition were assessed. RESULTS: The concentration and particle size of TiO2 significantly affected ΔE00 and ΔWID values, with the C1P100 group showing the greatest ΔE00 values and C1P100, C3P100, and C5P100 groups showing the greatest ΔWID values (p < 0.05). No significant changes were observed in surface microhardness, roughness, microstructure or composition (p > 0.05). CONCLUSIONS: Incorporating 1% TiO2 with a particle size of 100 nm into HP constitutes an effective bleaching strategy to achieve desirable outcomes.