The effect of polishing protocol on surface gloss of different restorative resin composites

Abstract

<p><b>Aim:</b> The purpose of this <i>in vitro</i> study was to determine the effects of different polishing protocols on the surface gloss (SG) of different commercial dental resin composites (RCs).</p><p><b>Material and methods:</b> A total of 147 block-shaped specimens (40 mm length × 10 mm width × 2 mm thick) were made from conventional RCs (G-aenial Ant. and Flo X), bulk-fill RC (Filtek Bulk Fill), fluoride-releasing RCs (BEAUTIFIL II, ACTIVA-Restorative) and discontinuous microfiber-reinforced RCs (Alert and everX Flow). Each group was subdivided into seven subgroups (<i>n</i> = 3), according to polishing protocol: Laboratory-machine polishing with different siliconcarbide paper grits (G1: 320) → (G2: 800) → (G3: 1200) → (G4: 2000) → (G5: 4000). Chairside-hand polishing using a series of Sof-Lex spiral (G6) and abrasive polishing points (G7). Glossmeter was used to determine the SG at 60° incidence angle. SG was measured before and after polishing. Three-dimensional (3 D) noncontact optical profilometer and scanning electron microscopy (SEM) analysis were performed. Data were analyzed using ANOVA (<i>p</i> = .05).</p><p><b>Results:</b> Significant differences in SG (ranged 3–93 GU) were found according to the type of polishing protocol and RC (<i>p</i> < .05). Specimens polished with 4000 grit paper showed the highest SG (93 GU) values among all the groups tested.</p><p><b>Conclusions:</b> The tested chairside-hand polishing protocols presented lower SG values than laboratory-machine polishing (4000 silicon paper grit) and unpolished surfaces.</p>