The Biomechanical Performance of Implant Screws with Different Biomaterials in Orthopedic Bone Fixation Procedures

Abstract

This study aimed to investigate the bone screwing process for stabilization following reduction of femur shaft fracture using M3.5 cortex screws made of four different materials: 316L stainless steel, Ti6Al4V, NiTi, and WC. The numerical analysis was performed using the finite element method and Deform-3D software, with loading and boundary conditions being accurately identified for each analysis. The screwing moment, screw wear, and temperature distributions in both the screw and bone material were evaluated for each material during the screwing process. The results showed that the lowest bone temperatures were achieved when using WC screws, followed by 316L, Ti6Al4V, and NiTi screws. The numerical simulations demonstrated good consistency across all four screw materials during the bone screwing process. The study used Finite Element Analysis to simulate screw insertion into sawbones. It employed tetrahedral elements for meshing, focusing on the hole area to mimic screwing accurately. Sawbones' lateral surfaces remained fixed, while the screw model experienced different spindle speeds and a constant feed rate. Contact between screw and sawbones was established using a master–slave algorithm, considering a friction coefficient of 0.42 to simulate frictional forces.