Effect of the calcium silicate and sodium phosphate remineralizing products on bleached enamel

This study evaluated the effect of calcium silicate and sodium phosphate (CSSP) dentifrice and serum on the surface of enamel bleached with hydrogen peroxide (H₂O₂).

A total of 160 bovine enamel slabs were bleached with 35% H₂O₂ and treated with sodium fluoride (NaF) dentifrice-GI, CSSP dentifrice-GII; CSSP dentifrice + CSSP serum-GIII, or NaF dentifrice + NaF gel-GIV. The dentifrices were applied using a brushing machine three times daily for 7 days. After brushing, sodium phosphate gel and CSSP serum were applied. The microhardness (KNH, n = 14), surface roughness (Ra, n = 14), energy dispersive spectroscopy (n = 6), and scanning electron microscopy (n = 6) were assessed at t₀ (before bleaching), t₁ (after bleaching), and t₂ (after postbleaching treatments).

The data were subjected to a two-way analysis of variance and Bonferroni's test.

The KNH decreased at t₁ (P < 0.001) but recovered at t₂ for all treatments, although only GII showed restored baseline values (P = 0.0109). The surface roughness increased at t₁ (P < 0.001) and reduced at t₂ (P < 0.001) for all groups, with no significant differences among groups. Enamel composition and morphology did not differ after the treatments, except for silicon accumulation in GIII.

Postbleaching treatment with CSSP dentifrice and serum yielded superior remineralizing effects on bleached enamel.