Effect of whitening dentifrices on the superficial roughness of esthetic restorative materials

Purpose: The purpose of this study was to investigate the surface roughness (Ra) of different esthetic restorative materials following simulated toothbrushing using different whitening dentifrices. Materials and Methods: Cylinders of Esthet-X (Dentsply Caulk, Milford, DE, USA), Durafil VS (Heraeus Kulzer, Wehrheim, Germany), and Vitremer (3M ESPE, St. Paul, MN, USA) were made using molds (4 mm in diameter for 2 mm in height). The superficial roughness was evaluated using a profilometer (Ra) with a cutoff length of 0.25 mm and a speed of 0.1 mm/s. The specimens (N = 13) were submitted to 7,500 brushing cycles using five different toothpastes: (1) Crest Regular (control; Procter & Gamble): silica abrasive (C); (2) Crest Extra Whitening (Procter & Gamble, Cincinnati, OH, USA): bicarbonate + calcium pyrophosphate (CE); (3) Dental Care A & H (Arm & Hammer, Camilla, GA, USA): bicarbonate (DC); (4) Rembrandt Plus Whitening (Oral B Laboratories, Belmont, CA, USA): carbamide peroxide + alumina/silica (RP); and (5) experimental: hydrogen peroxide + calcium carbonate (EX). Results: The data were analyzed by analysis of variance and Tukey's test (α = .05) for each restorative material, and the results [difference between final and initial roughness: Ra(F) - Ra(I) in μm] were as follows: Esthet-X: EX = 0.15 + 0.07^a; RP = 0.29 + 0.16^a; CE = 0.96 + 0.33^b; C = 1.03 + 0.29^b; DC = 1.48 + 0.37^b; Durafil VS: RP = 0.09 + 0.07^a; EX = 0.55 + 0.23^abc; C = 0.96 + 0.26^bc; CE = 1.03 + 0.33^cd; DC = 1.09 + 0.37 ^d; and Vitremer: EX = 0.10 + 0.08^a; RP = 0.26 + 0.19 ^a; CE = 0.94 + 0.27^b; DC = 1.13 + 0.46^bc; C = 1.50 + 0.32^C (different letters mean differences among groups). Conclusion: It was verified that the dentifrices containing carbamide or hydrogen peroxide along with alumina + silica and calcium carbonate, respectively (groups 4 and 5), produced minor changes in Ra when compared with the control group and with those dentifrices containing bicarbonate (groups 2 and 3).