Insights into advanced bone implants: optimising biocompatibility and mechanical performance in PEEK-HA composites

This research explores the impact of hydroxyapatite (HA) concentration on the mechanical properties and bioactivity of polyetheretherketone-hydroxyapatite (PEEK-HA) composites, aimed at optimising these materials for orthopaedic implants. Utilising a combination of experimental approaches and computational modelling, including Physics-Informed Neural Networks (PINNs), the study systematically investigates how varying hydroxyapatite content influences the evolving tensile strength, compressive strength, modulus of elasticity, and mineral deposition rates. Significant findings indicate that increasing the hydroxyapatite (HA) content from 10% to 40% results in a 16.7% reduction in tensile strength, decreasing from 90 MPa to 75 MPa, and a slight decline in the modulus of elasticity from 3.5 GPa to 3.2 GPa. Despite this reduction in mechanical properties, higher HA concentrations markedly enhance mineral deposition, indicating improved enhanced bioactivity–an essential factor for effective osteointegration. These results suggest that while elevated HA content may modestly compromise stiffness and tensile strength, it offers substantial benefits in applications where enhanced bioactivity and compressive strength are critical. The research confirms the potential of PEEK-HA composites to be tailored for specific biomedical applications, providing a foundation for developing advanced implant materials that offer improved bone replacement and regeneration outcomes.