Effect of Four Bleaching Regimens on Color Changes and Microhardness of Dental Nanofilled Composite. (14th October 2009)

• Record Type: Journal Article
• Authors: Silva Costa, Simone Xavier; Becker, Anne Buss; de Souza Rastelli, Alessandra Nara; Monteiro Loffredo, Leonor de Castro; de Andrade, Marcelo Ferrarezi; Bagnato, Vanderlei Salvador
• Other Names: Nikaido Toru Academic Editor.
• Is Part Of: International journal of dentistry. Volume 2009(2009)
• Publication Date: 2009-10-14
• Subjects: Dentistry -- Periodicals; Dentistry; Dentistry -- Periodicals; Electronic journals; Periodicals; 617.6
• DOI: 10.1155/2009/313845
• Languages: English
• ISSNs: 1687-8728

Abstract

Abstract : Objective . The purpose of this study was to compare the color changes and microhardness of a nanocomposite after four bleaching regimens. Materials . Twenty-five specimens( n = 25 ) were made with a nanocomposite resin (Filtek Supreme XT). The specimens were divided into five groups 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 made with spectrophotometer using CIELAB color scale. The Vickers hardness (VHN) measurements were performed at the top surface. The data were analyzed with two-way Analysis of Variance. Results .Δ E and VHN mean values into the groups were not statistically different, however, the VHN mean values before and after storage and bleaching showed statistically significant differences. Conclusion . Nanocomposite samples showed no significant alteration (color and microhardness) after bleaching. Thus, no replacement of restorations is required after bleaching.