3D-printed magnesium-doped micro-nano bioactive glass composite scaffolds repair critical bone defects by promoting osteogenesis, angiogenesis, and immunomodulation.

Magnesium ions play an important immune-regulatory role during bone repair. For this study, we prepared micro-nano bioactive glass (MNBG) containing magnesium, which can release magnesium, silicon, and calcium ions and has a positive impact on osteogenic differentiation and vascular regeneration. In this study, MgMNBG was compounded and combined with poly(lactic-co-glycolic acid (PLGA) and polycaprolactone (PCL) for 3D printing. Afterwards, the physicochemical properties and bone repair performance of the scaffolds were evaluated throughandexperiments. We also investigated the effects of MgMNBG on osteogenic differentiation, immune regulation, and vascular regeneration. The results showed that MgMNBG can inhibit inflammation and promote osteogenesis and angiogenesis by regulating macrophages. PLGA/PCL/MgMNBG scaffolds have good osteogenic and angiogenic effects, and the composite scaffolds have excellent bone repair performance and potential application value.