Investigation of surface roughness of acrylic based permanent denture made with 3D printer after applying standardized polishing methods

Abstract

Introduction: Acrylic resins have been widely used to construct all kinds of dental prostheses. Finishing and polishing the surface of the prosthesis to achieve smooth and highly polished surfaces is of great importance for the comfort of the patient and the longevity of the prosthesis. There are different methods for polishing the denture base; Considering the different effects of different polishing methods on the surface roughness of denture base materials, the purpose of this study is to investigate the surface roughness of standardized acrylic polishing methods made with a 3D printer. Materials and methods: 45 acrylic samples were made and used using a 3D printer. After the samples were prepared, all surfaces were cut with a tungsten carbide bur at a speed of 10,000 rpm. Then, using two mechanical polishing methods and one chemical polishing method, the polishing was done. The surface roughness of the samples was measured with an accuracy of micrometer by the device. The data obtained from the study were reported using descriptive statistical methods in the form of mean, standard deviation and frequency (percentage). In order to compare surface violence in three groups, one-way analysis of variance and post hoc tests (in case of normality of data) and Kruskal-Wallis and Mann-Whitney test (non-normal distribution of data) were used. SPSS.21 statistical software was used for data analysis. In this study, p value less than 0.05 was considered significant. Results: The roughness values of Ra and Rmax have a significant difference in the comparison of the three polishing methods, but the difference of the roughness values of Rz between the three polishing methods is not significant. The values of Ra in the polishing method are significantly lower than the chemical method, but there is no significant difference between the bur and sand paper method and the chemical method. Mechanical methods also do not have significant differences with each other. Regarding Rmax roughness, among the three polishing groups, the chemical method has the least roughness and the mechanical methods have no significant differences with each other. Conclusion: Among the three polishing methods examined in this study, the universal polishing method produces the lowest amount of surface roughness in acrylic resin.