Surface roughness evaluation of different novel CAD/CAM dental materials

Abstract

The aim of the study was to evaluate and compare surface roughness among different CAD/CAM dental materials when all materials are finished and polished according to the manufacturer's instructions. The 45 specimens were split into three groups: RBC (resin-based composite), ZR (zirconia) and CoCr4 (CoCr4 alloy). The surface roughness was evaluated using a mechanical profilometer, atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses. The data were analysed using the Kruskal-Wallis test with a Dunn's post hoc analysis and all data were presented as mean ± SD. Surface roughness analysis on a microscale (μm) revealed significantly higher Ra (μm) mean values in the ZR group compared to RBC and (p < 0.05) and CoCr4 group (p < 0.05), between which no statistically significant difference was observed (p > 0.05). Surface roughness analysis on a nanoscale (nm) has shown the opposite results, with the lowest values in the ZR group and statistically significant differences among all material groups (p < 0.05). AFM 3D and SEM 2D images revealed heterogeneous surface morphology for all groups.