Effect of In-Office Carbamide Peroxide-Based Tooth Bleaching System on Wear Resistance of Silorane-Based and Methacrylate-Based Dental Composites.
OBJECTIVE
Several studies have assessed the characteristics and properties of silorane-based composites and adhesive systems. Considering the extensive application of tooth-whitening agents, possible deteriorative effects of tooth bleaching agents on these restorative materials must be studied. The aim of this study was to evaluate the effect of an in-office carbamide peroxide-based tooth bleaching agent on the wear resistance of a silorane-based and a conventional microhybrid dimethyl methacrylate-based dental composite with two different application times.


METHODS
Thirty cylindrical specimens were made of Z250 and P90 dental composite resins (n=15 for each composite). Samples made of each composite were divided into three groups (n=5) for immersion in an in-office bleaching agent (Opalescence® Quick 45%) for either three or eight hours or saline solution (control). Wear tests were conducted after bleaching using a pin-on disk apparatus under the load of 40N at a constant sliding speed of 0.5 ms(-1) for a sliding distance of 300 m. The samples were weighed before and after the wear test. Repeated measures ANOVA was used to statistically analyze the obtained data (α=0.05).


RESULTS
There was a significant decrease in the weight of samples after the wear test (P<0.001). However, no significant difference was found among groups in the mean weight of samples before and after the wear test (P>0.05).


CONCLUSIONS
Bleaching for three or eight hours using 45% carbamide peroxide had no deteriorative effect on the wear resistance of Z250 and P90 composites.
Associate Professor, Dental Research Center, Dentistry Research Institute, Department of Restorative Dentistry, School of Dentistry, Tehran University Of Medical Sciences, Tehran, Iran.
Masoumeh
M
Hasani Tabatabaei
Assistant Professor, Orthodontics Department, Faculty of Dentistry, Babol University of Medical Sciences, Babol, Iran.
Sedigheh
S
Sheikhzadeh
Professor, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Iran.
Hamidreza
H
Ghasemi Monfared Rad
Polymer Engineering Department, Amir-Kabir University of Technology, Tehran, Iran.
Ahmad
A
Beygi
Assistant Professor, Dental Materials Research Center, Faculty of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Hossein
H
Bagheri
Carbamide Peroxide; Dental Restoration Wear; Silorane Composite Resin; Tooth Bleaching Agents