Influence of polishing methods on surface roughness and gloss of acrylic denture base resins

Abstract

This study investigated the influence of polishing methods on the surface roughness and gloss of three acrylic denture base resins. Two polishing methods were applied to the resin specimens: high polishing by laboratory lathe with pumice and rouge (HP) and chairside polishing kit with three silicone points (SP). Specimen preparation and surface polishing procedures were conducted to manufacturer’s recommendation. Surface roughness and gloss were measured by a contact type tester and a LED gloss checker with dual measurement mode (20°, 60°), respectively. Data were analyzed by one-way ANOVA and Scheffe’s post hoc test. P<0.05 was considered as significant. Within the limitation of this study, following conclusions were drawn. For all acrylic resins, HP method produced a significantly lower surface roughness (R<SUB>a</SUB>, R<SUB>y</SUB>, R<SUB>z</SUB>) than did SP method (P<0.05). SP procedure of specimens marked a higher surface roughness (R<SUB>a</SUB>) over the threshold roughness minimizing plaque attachment, 0.2 μm. Surface gloss units of specimens at 60° were higher than 20° illumination, but 20° gloss produced materials difference than 60° gloss. A strong negative correlation between all gloss units (8°/20°/60°) and Ra, 60° gloss showed the highest correlation coefficient.