The biological properties of 3D-printed degradable magnesium alloy WE43 porous scaffolds via the oxidative heat strategy

As a biodegradable material, magnesium alloy has a modulus similar to that of bone, and given the biological activity of its degradation products, it has the potential to be a bone grafting material. Oxidation heat treatment is a very effective passivation method that may reduce the rate of magnesium alloy degradation. Oxidation heat treatment increases the rare earth oxide content of the scaffold as well as the corrosion resistance of the scaffold. The overall cytotoxicity of the as-printed scaffolds (APSs) and oxidation heat-treated scaffolds (OHSs) showed that OHSs accelerated cell proliferation. In the apoptosis experiment, the OHS group had a cell survival rate between that of the control group and of the as-printed group. In the osteogenic induction experiment, the alkaline phosphatase activity and the quantity of mineralized nodules were greater in the APS and OHS groups than in the control group. Marker proteins for bone growth were expressed at higher levels in the APS and OHS groups than in the control group. Therefore, oxidation heat-treated 3D printing scaffolds with good biocompatibility and osteogenic properties have great potential to be made into advanced biomaterials that can be used to fix bone defects.