Influence of Thickener and Mineral Supplementation of Bleaching Gels on Enamel Demineralization

OBJECTIVE: This study evaluated the effect of the type of thickener and mineral supplementation of bleaching gels on enamel demineralization. MATERIALS AND METHODS: Enamel specimens were divided into five groups according to the type of thickener: CA-Carbopol, AE-Aerosil 200, PO-Poloxamer 407, GG-Guar gum, and HEC-Hydroxyethyl cellulose. Each group was subdivided into three subgroups according to the level of mineral supplementation: none, saturation concentration, and maximum addition. The microhardness (KHN), surface roughness (Ra), color change (ΔE00), and mineral content (DD) were measured before and after the treatment, and the changes were calculated. The data was analyzed with two-way ANOVA and Tukey's test. RESULTS: ANOVA showed significant differences among the groups (p < 0.05). The results of the Tukey test were: %KHN-HEC>GG>CA>PO>AE. %Ra-CA>HEC>PO>GG>AE. DE00-AE>GG>PO>HEC. %DD-HEC>PO>GG>CA>AE. The supplementation reduced the means of %KHN, %Ra, and %DD, without affecting the DE00. The effect of the supplementation level was not statistically significant. CONCLUSION: It was concluded that the type of thickener and the use of mineral supplementation significantly influenced the deleterious effects on the enamel.