This study evaluated the physical and mechanical properties of acrylic resins used for interim fixed prostheses, with and without metal reinforcement, before and after aging. A total of 138 samples were divided into three groups: VIPI + Wire (control), VIPI, and Diamond D. Samples were assessed for microhardness, porosity, roughness, and flexural strength. Aging was simulated using 500 thermocycling cycles at 5 and 55 ± 1 °C. Data were analyzed using ANOVA and Tukey’s test. Group Diamond D did not fracture during flexural testing, but it exhibited significantly lower microhardness at both baseline and after aging. Before aging, Group Diamond D had higher roughness than Group VIPI, which exhibited greater porosity. Aging increased the microhardness of Group VIPI and the roughness of Group Diamond D. The percentage of porosity decreased significantly for Groups VIPI + Wire and VIPI, and pore size was reduced in all groups. Based on the results obtained from Diamond D material, this resin does not meet the required properties for the proposed indication for temporary fixed prostheses, whereas VIPI with reinforcement showed superior properties and greater stability after aging.
Silva et al. (Tue,) studied this question.