The Effect of Three Polishing Systems on the Surface Rugosity of One Composite Resin

Direct restorations in composite resin require superficial rugosity appropriate to guarantee a surface free of biofilm buildup, which interferes with the durability of the restoration, its properties and the aesthetic aspect. Thus, it is relevant to know the behaviour of the finishing and polishing systems. The in vitro study aimed to compare the polishing efficiency of three different polishing systems in promoting the surface smoothness of a nanocomposite resin. Sixty specimens of the nanocomposite resin Filtek Z350 XT (3M) were made, randomly divided into three groups (n=20), according to the tested polishing systems: Enhance (Dentsply), DFL Polishers, and Sof-Lex Spiral (3M). The surface rugosity of the samples was measured by means of the rugosimeter equipment. The data were analysed through statistical tests: ANOVA two-way and post-hoc Tukey. The results indicated Sof-Lex (3M) polishing discs as the ones with the lowest average surface rugosity (0.13µm), presenting statistically significant results (p<0.05); followed by the abrasive rubbers of the DFL system (0.17 µm) and the Enhance system (Dentsply), which showed greater average surface rugosity (0.30 µm). The lowest surface rugosity of the composite resin evaluated in this study (Z350 XT- 3M) was obtained after polishing with the multi-step system (Sof-Lex), from the same manufacturer.