Comparative Evaluation of Three-dimensional-printed and Conventional Heat-cure Polymethyl Methacrylate Denture Base Materials

INTRODUCTION: The introduction of three-dimensional (3D) printing in prosthodontics has revolutionized denture fabrication. However, the concerns remain regarding the mechanical and physicochemical properties of 3D-printed polymethyl methacrylate (PMMA) in comparison to conventional materials. This research was done to evaluate and compare the physicochemical and mechanical properties of a novel 3D-printed PMMA-based denture base material with conventional heat-polymerized PMMA. MATERIALS AND METHODS: An in vitro experimental study was conducted on 98 specimens divided into two groups (n = 49 each): Group I (3D-printed PMMA) and Group II (conventional PMMA). Specimens were fabricated using standardized protocols and evaluated for flexural strength, water sorption, surface roughness, surface hardness, impact strength, and solubility as per ISO guidelines. The obtained data were statistically evaluated. RESULTS: Group II demonstrated significantly higher mechanical properties, including flexural strength (92.63 ± 7.54 MPa), hardness (22.74 ± 2.01 VHN), and impact strength (4.05 ± 0.52 kJ/m2) compared to Group I. Conversely, Group I exhibited higher surface roughness (0.42 ± 0.06 μm), water sorption (28.75 ± 3.21 μg/mm3), and solubility (2.94 ± 0.51 μg/mm3). All differences were statistically highly significant (P < 0.001). Strong negative correlations were found between physicochemical and mechanical parameters. CONCLUSION: Although 3D-printed PMMA offers advantages in digital dentistry, its inferior mechanical properties and higher degradation potential limit its current clinical applicability.