Avaliação das propriedades físicas e mecânicas de resina acrílica confeccionada por métodos inovadores de polimerização e submetida à termociclagem

• Autor(a) principal: Penitente, Paulo Augusto [UNESP]
• Data de Publicação: 2018
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/203966; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2019-04-18/000913575.pdf
• topic: Resinas acrílicas; Polimetil metacrilato; Dureza; Acrylic resins

Acrylic-based resin is the material of choice for making definitive and provisional prostheses and, in order to achieve its clinical success, it is important to know the most suitable polymerization process for this material. The aim of this study was to evaluate the influence of different polymerization methods on several physical and mechanical properties, before and after thermocycling, and on the degree of conversion (DC) of a heat-activated acrylic resin (HAAR). Ninety HAAR samples were divided into three groups: conventional polymerization (CP), dry-heat polymerization (DHP), and digital pneumatic polymerization (DPP). Color and microhardness tests (n=10) and flexural strength tests (n=20) were performed before and after 2000 cycles of thermocycling. The analysis of DC was performed by using Fourier transform infrared spectroscopy (n=4). Color alteration and DC data were submitted to one-way analysis of variance (ANOVA). Microhardness and flexural strength data were submitted to two-way repeated measures ANOVA. All results were submitted to the Tukey test (α =.05). The color alteration was statistically lower in the DHP group. The DPP group exhibited higher initial microhardness, with a statistically significant difference from other groups. There was no statistical difference between groups in regards to flexural strength. The CP and DPP groups had a higher DC. The proposed polymerization methods had divergent results for the different properties analyzed. However, these results were similar to those of conventional polymerization, which is a viable and adequate alternative