3D printing and physicochemical and biological characterizations of gallium-containing magnesium/calcium phosphate ceramic scaffolds

In this study, gallium-containing magnesium/calcium phosphate ceramic scaffolds (G-MCP) were prepared by sintering the mixtures of gallium-doped tricalcium phosphate and trimagnesium phosphate at low temperatures (950 and 1000 °C), and their pore structure was formed by the extrusion-type 3D printing method. The G-MCP ceramic scaffolds were dominated by the gallium/magnesium-doped Ca3Mg3(PO4)4 phase. The G-MCP ceramic scaffolds sintered at 950 °C attained considerably high compressive strength (5.0–13.2 MPa) as well as porosity (63.7%–72.1%). When the sintering temperature increased to 1000 °C, the G-MCP ceramic scaffolds achieved tremendous increase in compressive strength (38.3–94.3 MPa), which was concomitant with significant decrease in porosity (46.2%–48.7%). Benefiting from the release of gallium, magnesium and calcium ions, the G-MCP ceramic scaffolds noticeably stimulated in vitro cell growth and osteoblastic differentiation, and distinctively obstructed the osteoclastic differentiation. The G-MCP ceramic scaffolds are promising for effectively treating the osteoporotic bone defects.