Wear Resistance of Packable Resin Composites after Simulated Toothbrushing Test

ABSTRACT Purpose:: The purpose of this study was to determine the wear resistance of five different packable composites versus two different composite controls using a laboratory toothbrushing simulation test. Materials and Methods: Twelve samples measuring 5 mm in diameter and 3 mm thick were prepared from the following resin composites: Packable resin composites SureFil® (Dentsply Ind. Com. Ltda, Petrópolis, Rio de Janeiro, Brazil), Alert® (Jeneric Pentron Incorporated, Wallingford, CT, USA), Filtek P60™ (3M ESPE Dental Products, St. Paul, MN, USA), Prodigy Condensable® (sds Kerr, Orange CA, USA), Solitaire® (Heraeus Kulzer GmbH, Wehrheim, Germany), and control resin composites Z100 Restorative™ (3M ESPE) and Silux Plus™ (3M ESPE). Finishing and polishing were conducted with Sof‐Lex™ disks (3M ESPE), and baseline weight (grams) and surface roughness (measured with Hommel Tester® T 1000, Hommelwerke, GmbH, Alte Tuttinger Strebe 20. D‐7730 VS‐Schwenningen, Germany) were recorded. Specimens were aged for 2 weeks until they reached a weight that remained constant for 5 consecutive days, and then were subjected to 100,000 cycles of brushing (representative of 4.2 yr) using a toothbrushing testing machine. Toothbrush heads with soft bristle tips (Colgate Classic™, Colgate‐Palmolive Co., Osasco, São Paulo, Brazil) with dentifrice suspension (Colgate MFP™, Colgate‐Palmolive Co.) in deionized water were used under a 200 g load. Changes in weight and surface roughness were determined after toothbrushing cycles. Results: Significant differences of weight loss and surface roughness were found (paired t‐test, p < .05). Weight loss percentage (mean [SD]) ranged from 0.38 to 1.69% (analysis of variance and Tukey's least significant difference, p < .05); the weight loss of the materials ranked from least to most as follows: SureFil (0.38 [0.56]), Alert (0.52 [0.18]), Z100 (1.16 [0.27]), Filtek P60 (1.31 [0.17]), Solitaire (1.51 [0.45]), Prodigy Condensable (1.55 [0.47]), and Silux Plus (1.69 [0.66]). Regarding surface roughness, Prodigy Condensable (0.19 [0.08]), Solitaire (0.28 [0.06]), and Z100 (0.30 [0.07]) became less rough after toothbrushing, whereas all the others were rendered rougher: Alert (0.49 [0.29]), Filtek P60 (0.28 [0.08]), Silux Plus (0.39 [0.09]), and SureFil (0.81 [0.32]). Conclusion: SureFil and Alert were statistically more resistant to wear (less weight loss) than were the other materials. SureFil became significantly rougher than did all the other