Estudo da rugosidade de superfície de diferentes resinas acrílicas

Abstract

INTRODUCTION: PMMA has been commonly used as a material for denture bases. Inherent disadvantages led to the emergence of various resins to overcome some problems as the CAD/CAM technology. Among the properties of materials used in making dental prostheses, surface properties such as roughness have high clinical relevance, since a prosthetic base with greater roughness will enhance the development of pathologies such as Oral Candidiasis or Prosthetic Stomatitis, which are the most prevalent inflammatory diseases in patients with removable dentures. The main objective of this laboratory investigation study is to determine the effect of the same polishing protocol on the surface roughness of different prosthetic base resins obtained by different processing techniques. METHODOLOGY: Thirty acrylic resin specimens obtained by different processing methods were manufactured. The specimens were submitted to the same polishing protocol using two different techniques, manual and mechanized. The surface roughness was measured by a contact profilometer. Data were submitted to statistical analysis using the SPSS program with a significance level set to 0.05. RESULTS: All resins subjected to manual polishing had an average roughness value significantly lower than resins submitted to mechanized polishing, except for thermoplastic resins (p=0.713). For resins subjected to manual polishing, there were significant differences between the resin pairs milling and 3D printing (p=0.012) and thermopolymerizable and milling (p=0.24). In the case of resins subjected to mechanized polishing, there were only significant differences regarding the roughness values between the self - cured and 3D printed resins (p=0.004) and self-cured and thermopolymerizable resins (p=0.004). CONCLUSION: When the same polishing protocol is applied, the difference in the surface roughness value between acrylic resins for making prosthetic bases can be attributed to the inherent characteristics of the resin and the respective processing techniques.

Date of Award	13 Jul 2022
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Patrícia Fonseca (Supervisor), Helena Cristina Morais Coelho Teixeira Salgado (Co-Supervisor) & Carlos Fernandes (Co-Supervisor)