Effect of different polishing methods applied to denture base materials on microbial adhesion and surface roughness

Aim: The aim of our study was to investigate the effect of various polishing processes applied to different types of PMMA (polymethyl methacrylate) denture base materials on the surface roughness and microbial adhesion of the base material. Methods: Sixty specimens each were prepared from heat-polymerized conventional PMMA (G), heat-polymerized injectable PMMA (E), and prepolymerized CAD/CAM PMMA (C) denture base materials. All sample surfaces were sanded with 800, 1000, 1200, and 2500 grit silicone carbide abrasives. The specimens of each denture base material were divided into three subgroups (n=20) in which different polishing methods were applied. The first group was mechanically polished (M), and the other two groups were chemically polished with light polymerized glaze liquids [Palaseal (Ps), Optiglaze Color (Og)]. A profilometer device was used to evaluate the surface roughness. Colony counting was performed to evaluate bacterial colonization after one day. The data obtained from all these measurements were evaluated using an analysis of variance, and Bonferroni corrected test was used for multiple comparisons of means (p=0.05). The interaction between surface roughness and bacterial colonization was examined by the Pearson correlation test. Regression analysis was performed to determine the relationship between them. Results: When PMMA base materials were compared, the lowest average surface roughness (Ra) values and bacterial colonization values were obtained in Group C. When polishing methods were compared, the lowest average surface roughness values were obtained in Group M. As a result of bacterial colonization measurement, lower colonization values were obtained with standardized mechanical polishing compared to other groups. Conclusion: There was no difference between the different PMMA base materials in terms of surface roughness, but there were statistical differences in bacterial colonization. The results of our study showed that mechanical polishing gave better results than light-activated glazing agents. How to cite this article: Yarar S, Değer Y, Tekin S. Effect of different polishing methods applied to denture base materials on microbial adhesion and surface roughness. J Med Dent Invest 2023; 4: e230351. https://doi.org/10.5577/jomdi.e230351