3D printed polylactic acid/polyethylene glycol/bredigite nanocomposite scaffold enhances bone tissue regeneration via promoting osteogenesis and angiogenesis.

Recently, the fabrication of personalized scaffolds with high accuracy has been developed through 3D printing technology. In the current study, polylactic acid/polyethylene glycol (PLA/PEG) composite scaffolds with varied weight percentages (0, 5, 10, 20 and 30 %) of bredigite nanoparticles (B) were fabricated using the 3D printing and then characterized through scanning electron microscopy and Fourier transform infra-red spectroscopy. The addition of B nanoparticles up to 20 wt% to PLA/PEG scaffold increased the compressive strength (from 7.59 to 13.84 MPa) and elastic modulus (from 142.42 to 268.33 MPa). The apatite formation ability as well as inorganic ion release in simulated body fluid were investigated for 28 days. The MG-63 cells viability and adhesion were enhanced by increasing the amount of B in the PLA/PEG scaffold and the osteogenic differentiation of the rat bone marrow mesenchymal stem cells was confirmed by alkaline phosphatase activity test and alizarin red staining. According to chorioallantoic membrane assay, the highest angiogenesis occurred around the PLA/PEG/B30 scaffold. In vivo experiments on a rat calvarial defect model demonstrated an almost complete recovery in the PLA/PEG/B30 group within 8 weeks. Based on the results, the PLA/PEG/B30 composite scaffold is proposed as an optimal scaffold to repair bone defects.