Evaluation of Enamel Surface Properties Submitted to Bleaching With 35% Hydrogen Peroxide Associated With Titanium Tetrafluoride (TiF₄)

Objective: This study evaluated the color change, surface roughness, mineral content and morphology of enamel bleached with 35% hydrogen peroxide (HP) combined with an experimental gel containing 1% titanium tetrafluoride (TiF₄).

Materials and methods: Bovine enamel blocks were treated with (n = 12): (TiF) experimental gel containing 1% TiF₄, (HP) 35% HP, (HPT) 35% HP + 1% TiF₄ and (CT) control. Bleaching with HP was performed in 3 sessions (3 × 15 min/applications). pH, colorimetric parameters, surface roughness, mineral content and enamel morphology were determined. The pH was evaluated for 45 min. The color parameters were determined before bleaching (T₀), and 14 days elapsed from the last bleaching session (T₄). Surface roughness was analyzed at T₀ and immediately after last bleaching session (T₃). Enamel mineral content and morphology were verified at T₄. Data were statistically analyzed by one-way, two-way ANOVA and Kruskal-Wallis (α = 0.05).

Results: TiF increased surface roughness, and no differences between HP and HPT in terms of color and ${\mathrm{CO}}_3^{2-}$ - ${\mathrm{PO}}_4^{3-}$ mineral content. Ti was detected only on TiF, and slight surface morphology changes were observed in bleached enamel.

Conclusions: The combination of TiF₄ and 35% HP did not interfere with the enamel bleaching effect, controlled surface roughness, and kept mineral content but promoted a minor surface morphology alteration.

Clinical significance: Due to the adverse effects of bleaching, titanium tetrafluoride (TiF₄) has gained attention for its therapeutic properties, including the ability to reverse mineral loss and neutralize remineralization of mineral structures. Therefore, TiF₄'s remineralizing capacity may be a good alternative for incorporation into hydrogen peroxide bleaching agents.