In-vitro evaluation of surface properties and early bacterial adhesion in cad/cam resin materials for provisional restorations

Objectives: The aim of this study was to determine the effects of surface roughness and material type on bacterial adhesion to provisional resin materials. Materials and Methods: Standardized specimens of six different materials were fabricated using a stainless-steel mould/computer-aided design/computer-aided manufacturing (CAD/CAM) system. A profilometer was used to measure surface roughness. Each group was divided into two subgroups, which were treated with Streptococcus mutans and Candida albicans suspensions, respectively. Bacterial adhesion was assessed using a confocal laser microscope. Differences in surface roughness in independent groups were evaluated with the Kruskal–Wallis test, and multiple comparisons were performed using Wilcoxon rank sum tests. Bacterial data were analysed using the analysis of variance F test, with multiple comparisons using Tukey’s honestly significant difference test. Results: The main result can be briefed as; surface roughness differed significantly among groups. Composite resin CAD/CAM blocks showed greater surface roughness and vital bacterial adhesion than did the other materials. Conclusions: Surface smoothness is important for provisional restorations, as plaque accumulation and diffusion of allergenic elements to these restorations is greater than that to natural tooth surfaces. If provisional crowns are to be used in the long term, this should be taken into consideration.