Improving mechanical strength and osteo-stimulative capacity of 3D-printed magnesium phosphate ceramic scaffolds by magnesium silicate additives

Magnesium phosphate ceramics are short of osteostimulation capacity to effectively repair the bone defects. Herein, magnesium silicate (MgSi) was utilized as an additive to modify the 3D-printed magnesium phosphate (MgP) ceramic scaffolds. The results presented that the addition of MgSi was conducive to enhancement of compressive strength of the MgP/MgSi ceramic composite scaffolds, and the scaffolds incorporating 20 wt% MgSi had the highest value. The degradation of MgP/MgSi scaffolds resulted in a decrease of mechanical strength and the continuous release of magnesium and silicon ions. In comparison with MgP scaffolds, the MgP/MgSi scaffolds promoted the growth and osteogenic gene expression of bone marrow mesenchymal stem cells. Collectively, the 3D-printed MgP/MgSi scaffolds with high mechanical strength and osteo-stimulation effects are potential biomaterials for the effective restoration of bone defects.