Effect of Zn-nanoHA concentration on the mechanical performance and bioactivity of 3D printed PEEK composites for craniofacial implants

Abstract

This study aims to investigate the mechanical performance and bioactive potential of polyetheretherketone (PEEK)-based composites. PEEK powder is mixed with up to 20 wt-% zinc doped nano-hydroxyapatite (ZnHA) powder to extrude filaments. Subsequently, 3D-printed samples are prepared via fused deposition modelling (FDM). Micro-Computed Tomography (µ-CT) analysis shows the distribution of ZnHA particles in extruded filaments. Fourier transform infrared spectroscopy (FTIR) confirms the functional groups in 3D-printed samples. The tensile testing results showed that at higher concentration of ZnHA, the strength and strain at failure decrease, while the elastic modulus increases within the acceptable range of human cortical bone. Bioactivity tests in simulated body fluid (SBF) for up to 14 days illustrate the formation of apatite precipitates on the composite samples’ surface compared to pure PEEK. Based on the results, it can be concluded that FDM 3D-printing of PEEK/ZnHA composites can be used effectively in manufacturing customised craniofacial/orthopedic implants.