Biomechanical evaluation of mesh-based mandibular reconstruction plates and their implication for temporomandibular joint prosthesis

Mandibular reconstruction involving the temporomandibular joint (TMJ) presents clinical challenges due to the need for both structural integrity and joint function. This study developed and biomechanically evaluated patient-specific mandibular reconstruction plates integrated with TMJ prostheses, focusing on mesh-based designs as an alternative to the conventional solid plate. The samples studied in this work included the conventional plate (CON-plate) and the mesh-based variants with relative densities (RD) from 0.2 to 1.0, fabricated using metal additive manufacturing. Finite element analysis (FEA) was validated with experimental compression tests, showing strong agreement in resulting stiffness, where both results differed by <7%. Under simulated masticatory loading, mesh-based plates demonstrated more uniform stress distribution, reducing peak stresses in both plates and screws by approximately 60%. In addition, an effective stress parameter was introduced to indicate mechanical efficiency relative to mass, demonstrating that the mesh-based plates achieve an improved stress–mass trade-off than the conventional design. Additionally, tribological testing showed that post-processing of Ti-6Al-4 V pins reduced UHMWPE wear rate from 1.44 × 10^–4 mm³/Nm to 1.21 × 10^–4 mm³/Nm, highlighting the importance of surface finish. Integration of mesh-based plates also lowered von Mises stress and contact pressure in UHMWPE fossa components, indicating reduced wear potential. Overall, the mesh-based reconstruction plates present a promising strategy to enhance load transfer, minimize implant wear, and improve long-term outcomes for both mandibular reconstruction and TMJ prosthesis.