3D printing of personalized magnesium composite bone tissue engineering scaffold for bone and angiogenesis regeneration

Critical-size trabecular bone defects remain challenging to treat in orthopedic clinical practice. This study utilized a polyethylene glycol dispersion method to uniformly disperse magnesium (Mg) and nano-hydroxyapatite (n-HA) in a polylactic acid (PLA) solution, resulting in the fabrication of an Mg/n-HA/PLA composite material. We next generated personalized bone repair scaffolds through Fused Deposition Modeling (FDM) 3D printing. The composite scaffolds were characterized, and their biocompatibility, osteogenic properties, and angiogenic capabilities were assessed through in vitro experiments. In vivo experiments were conducted to explore the pathways underlying osteogenesis and angiogenesis. The results confirmed that the properties and biological efficacy of the Mg composite material could be regulated by controlling the quantitative ratio of Mg. The results showed that the 10 % Mg composite group exhibited optimal osteogenic properties, whereas the 20 % Mg composite group showed the best angiogenic effects and the most promising induction properties. The beneficial effect of the composite scaffold was associated with the interconnected REK and FAK/HIF-1/VEGF signaling pathways. In conclusion, the Mg composite biomaterial exhibited desirable processability, mechanical properties, and degradability, and induced osteogenesis and angiogenesis. These features of composite scaffold meet the complex requirements for treating critical-size trabecular bone defects in load-bearing animals and having potential for clinical development and application.