Effect of Polishing Procedure on the Roughness and Bacterial Adhesion of Provisional Restorative Materials

Abstract

Provisional prosthetic restoration materials are exposed to oral cavity producing on the surface biofilm where different factors such as surface roughness and porosity can condition their formation and organization and can create stagnation areas that promote the bonding of organic particles, thus facilitating the formation and maturation of the biofilm. The purpose of this study was to compare surface roughness of two provisional prosthetic restorations materials and their bacterial susceptibility. In this study, two provisional restoration materials were used in two groups, A polymethyl methacrylate acrylic (NicTone MDC DENTAL) and B bis-acryl resin (Protemp 4 ESPE 3M). A total of 80 samples (40 samples of each material) were in thick plates of 10 × 10 mm and 2 mm high. 20 samples of each material were polished, while 20 were left unpolished. Subsequently, the samples were observed by Atomic Force Microscopy for their evaluation of surface roughness. The values were analyzed with t-test, Mann-Whitney U test and Kruskal Wallis test. The samples were microbiologically inoculated with the strains obtained and identified from a provisional polymethyl methacrylate acrylic restoration in a patient, in order to observe bacterial adhesion using a Scanning Electron Microscope. Two strains, Enterococcus faecalis and Pseudomona luteola, were identified. The presence of the microorganisms was observed on the surface of both materials, either polished or unpolished, with a lower level of microorganism adhesion found on the bis-acrylic resin. There was a significant difference about surface roughness in the groups A and B with p -8). We found that the polished bis-acrylic resin showed lower surface roughness and bacterial adhesion in comparison with the polymethyl methacrylate.