Biomechanical Analysis of Mandibular Bone-Implant Construct with Three Implant Screw Design: A Finite Element Study

Temporomandibular joint replacement (TMJR) is a surgical procedure that relies heavily on the biomechanical properties of the implant-bone interface for success. In this study, we investigated the effects of three commonly used implant screw thread designs (buttress, square, and triangle) on the biomechanical performance of the mandibular bone-implant construct, with the aim of improving osseointegration. Using finite element analysis, we simulated the mechanical behavior of the prosthesis and mandible and examined the biomechanics of the temporomandibular joint. We considered five coefficients of friction ranging from 0.1 to 0.5 in our analyses. Our hypothesis was that changing the screw thread shape while keeping the pitch, height, and depth constant could enhance the biomechanical environment at the peri-implant bone. Our results indicate that the square thread design produced the highest stress concentration, while the triangle thread design exhibited the most favorable distribution of stress around the implant. Furthermore, increasing the coefficient of friction led to an increase in stress concentration in the implant and surrounding bone. Our findings offer valuable insights into the biomechanical performance of different screw thread designs in the mandibular bone-implant construct. They highlight the significance of considering screw thread shape and coefficient of friction in TMJR implant design. Future studies should incorporate the viscoelastic properties of bone to improve the accuracy of finite element analysis. This research contributes to the optimization of TMJR implants and ultimately enhances patient outcomes.