Evaluating the effect of printing parameters on the performance of resin occlusal splints for a sustainable dentistry.

Bruxism affects millions worldwide, leading to dental damage like worn teeth and tooth loss. Resin 3D printing presents a promising method for creating intricate, comfortable, and durable occlusal splints. This study examines how printing parameters-layer thickness, orientation angle, and curing time-affect the mechanical (compressive strength, wear rate, impact strength) and physical (water sorption, surface roughness, dimensional accuracy) properties of occlusal splints made from a methacrylate-based resin. A total of 120 specimens were produced according to American Society for Testing and Materials (ASTM) standards using different parametric combinations. The response surface methodology (RSM) was applied to optimize key parameters. The optimum printing parameters for compressive strength include a layer height of 16.5 mm, curing time of 93.6 min, an orientation angle of 12.8º, yielding a compressive strength of 9.05 MPa, wear rate of 159 mm/min, and impact strength of 71.58 J/m. Similarly, the optimum results for minimum surface roughness (8.013 microns), maximum dimensional accuracy (97.67 and minimum water sorption (0.386%) are achieved at a layer thickness of 16 mm, curing time of 93 min, and orientation angle of 12º. Results show that optimizing resin 3D printing parameters for occlusal splints significantly reduces production costs, particularly in regions with limited access to dental care, while promoting sustainable dental solutions by minimizing the environmental impact of traditional manufacturing methods and enhancing the efficiency of splint production.