Effect of Four Bleaching Regimens on Color Changes and Microhardness of Dental Nanofilled Composite

[摘要] Objective. The purpose of this study was to compare the color changes and microhardness of ananocomposite after four bleaching regimens.Materials. Twenty-five specimens(n=25)were made with a nanocomposite resin (Filtek Supreme XT). The specimens were divided into fivegroups equally(n=5): bleaching groups and control group, as follows: G1: artificial saliva at37∘C; (control) G2: hydrogen peroxide (HP) at 7%; G3: hydrogen peroxide (HP) at 35%; G4: carbamide peroxide (CP) at 10%; G5: carbamide peroxide (CP) 35%. Color measurements were madewith spectrophotometer using CIELAB color scale. The Vickers hardness (VHN) measurementswere performed at the top surface. The data were analyzed with two-way Analysis of Variance.Results.ΔE and VHN mean values into the groups were not statistically different,however, the VHN mean values before and after storage and bleaching showed statisticallysignificant differences.Conclusion. Nanocomposite samples showed no significant alteration(color and microhardness) after bleaching. Thus, no replacement of restorations is required afterbleaching.

[学科分类] 口腔科学