Comparison of flexural strength of denture base made with two methods of heat-cure and 3D printer with and without thermocycling

Abstract

Purpose: One of the critical and unknown properties of new acrylic resins is their flexural strength. This study investigated the flexural strength of PMMA resin denture base fabricated with a 3D printer and compared it with a conventional heat-cured resin. Materials and methods: In this in vitro study, 40 cuboid samples were prepared from two types of acrylic resin, with a thickness of 4 mm and dimensions of 10×80 mm. Half of the samples in each group were thermocycled; then, the flexural strengths of the samples were determined using the three-point bending test. The data were analyzed with SPSS 22 using two-way ANOVA and independent t-test at a significance level of 0.05. Results: The mean flexural strengths of the Detax 3D printer and heat-cured Meliodent resin samples were 66.26±7.6 and 87.32±8.8 MPa, respectively. Conclusion: Heat-cured resin's mean flexural strength was higher than the resin fabricated with the 3D printer, with no significant difference in the mean flexural strength in the presence or absence of thermal stress. Flexural strength values in both resins were clinically acceptable (65 MPa) based on ISO standards.