The mechanical properties and bioactivity of Ti-Mg composites as orthopedic implants: A pilot study

Stress shielding effects and bioinertia are two main problems of titanium alloy orthopedic implants, which are commonly used in clinical therapy. By adjusting the porosity of the Ti alloy, the stress shielding effects can be avoided and the strength of the titanium alloy is also significantly decreased. To improve the mechanical property and bioactivity, Ti-Mg composites were fabricated by pressureless infiltration and 3D printed. Excellent mechanical properties, biocompatibility and bioactivity of the Ti-Mg composites were demonstrated by in vitro and in vivo results. The ultimate compressive strength and compressive yield strength could be increased to 292.5 +/- 10.0 MPa and 27.9 % 220.0 +/- 11.5 MPa, respectively. Furthermore, the bioactivity of Ti-Mg composites was also significantly improved due to the release of Mg ions during the degradation process, which can promote osteoblast adhesion and differentiation.