Abstract: Objective:?To investigate the physicochemical properties and osteoinductive potential of magnesium phosphate scaffold with two different scale pores prepared by 3D printing technology and porogen leaching. Methods: Magnesium phosphate scaffolds (MgP) were prepared by indirect printing method. We used sodium chloride (particle size 25-50 μm) as porogen to fabricate microporous magnesium phosphate scaffolds (MgP-Na). The physical and chemical properties of magnesium phosphate scaffolds were examined by scanning electron microscopy, mercury porosimetry, general material testing machine and X-ray diffraction. CCK8 and DAPI staining were used to detect the proliferation and adhesion of human bone marrow mesenchymal stem cells (hBMSCs) seeded on scaffolds. Alizarin red staining and alkaline phosphatase quantitative assay were used to evaluate the ability of scaffolds to promote the osteogenic differentiation of hBMSCs. Results:MgP-Na scaffolds showed higher porosity, and the micropores significantly reduced the compressive strength of MgP-Na scaffolds (P＜0.05). Both scaffolds possessed excellent biocompatibility, and hBMSCs can adhere and proliferate on the scaffolds (P＜0.05). Moreover, the microporous structure was more conducive to cell adhesion. MgP-Na scaffolds played a more active role in calcium deposition and osteogenic differentiation of hBMSCs seeded on scaffolds (P＜0.05). Conclusions: Magnesium phosphate scaffold is expected to be a new material for bone defects repairing. The microporous structure of MgP-Na scaffold plays a more effective role in osteoinduction.

Key words: magnesium phosphate;?bioceramic scaffolds;?3D printing;?porosity, ?osteoinduction