Dental 3D-printing technologies, including stereolithography (SLA), polyjet (triple-jetting technology), and fusion deposition modeling, have revolutionized the field of orthodontic occlusal splint manufacturing. Three-dimensional printing is now currently used in many dental fields, such as restorative dentistry, prosthodontics, implantology, and orthodontics. This study aimed to assess the mechanical properties of 3D-printed materials and compare them with the conventional polymethylmethacrylate (PMMA). Compression, flexural, and tensile properties were evaluated and compared between PMMA samples (n = 20) created using the "salt and pepper" technique and digitally designed 3D-printed samples (n = 20). The samples were subjected to scanning electron microscope analysis. Statistical analysis revealed that the control material (PMMA) exhibited a significantly higher Young's modulus of compression and tensile strength (p < 0.05). In the flexural tests, the control samples demonstrated superior load at break results (p < 0.05). However, the 3D-printed samples exhibited significantly higher maximum bending stress at maximum load (MPa) (p < 0.05). Young's modulus of tensile testing (MPa) was statistically significant higher for the control samples, while the 3D-printed samples demonstrated significantly higher values for elongation at break (p < 0.05). These findings indicate that 3D-printed materials are a promising alternative that can be effectively utilized in clinical practice, potentially replacing traditional heat-cured resin in various applications.
Keywords: 3D printing; mechanical properties; occlusal splint; polyjet; polymethylmethacrylate (PMMA); scanning electron microscopy (SEM).