Impact of a novel polishing method on the surface roughness and micromorphology of nanofilled and microhybrid composite resins

Abstract

ObjectiveThis study aimed to evaluate the effects of different finishing and polishing techniques, including a novel polishing method (silicon carbide brush), on the surface roughness and morphology of nanofilled (Filtek Z350XT) and microhybrid (Filtek Z250) composite resins. MethodsThirty-five specimens of each resin were fabricated and assigned randomly to receive the following finishing/polishing treatments (n = 5 per group): none (control), Sof-Lex Pop-On discs (POP), Praxis discs (PRA), POP + felt discs with diamond paste, POP + silicon carbide brush, PRA + felt discs with diamond paste, and PRA + silicon carbide brush. Average roughness (Ra) in μm was evaluated using a 3D profilometer. Scanning electron microscopic images were also obtained and descriptively analyzed. Two-way analysis of variance and Tukey's test (p < 0.05) were used to evaluate the effects of resin type, finishing/polishing system, and interactions between these two variables on Ra values. ResultsFor the microhybrid resin, greater surface smoothness was obtained using POP or PRA + silicon carbide brush. For the nanofilled resin, the smoothest surface was obtained with POP + felt discs with diamond paste or silicon carbide brush. ConclusionThe surface roughness of a composite resin depends on its composition and finishing and polishing technique used.