Abstract
CONTEXT AND AIMS: This study evaluated the effect of calcium silicate and sodium phosphate (CSSP) dentifrice and serum on the surface of enamel bleached with hydrogen peroxide (H(2)O(2)). MATERIALS AND METHODS: A total of 160 bovine enamel slabs were bleached with 35% H(2)O(2) 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 t(0) (before bleaching), t(1) (after bleaching), and t(2) (after postbleaching treatments). STATISTICAL ANALYSIS USED: The data were subjected to a two-way analysis of variance and Bonferroni's test. RESULTS: The KNH decreased at t(1) (P < 0.001) but recovered at t(2) for all treatments, although only GII showed restored baseline values (P = 0.0109). The surface roughness increased at t(1) (P < 0.001) and reduced at t(2) (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. CONCLUSIONS: Postbleaching treatment with CSSP dentifrice and serum yielded superior remineralizing effects on bleached enamel.