Fabrication and biological evaluation of porous β-TCP bioceramics produced using digital light processing.

Beta-tricalcium phosphate (β-TCP) refers to one ideal bone repair substance with good biocompatibility and osteogenicity. A digital light processing (DLP)-system used in this study creates bioceramic green part by stacking up layers of photocurable tricalcium phosphate-filled slurry with various β-TCP weight fractions. Results show that the sintering shrinkage is anisotropic and the shrinkage vertically reaches over that horizontally. The obtained porous β-TCP parts have both macroporous outer structure and microporous inner structure, the macropore size is 400-600 μm and the micropore size is 500-1500 nm. The mechanical tests show that the porous β-TCP bioceramic's compressive strength reaches 16.53 MPa. The cell culture confirmed that the porous β-TCP bioceramic is capable of achieving the effective attaching, growing, and proliferating pertained to mouse osteoblast cells. This study identified considerable blood vessels and significant ectopic bone forming obviously based on the histologically-related assessment when implanting to rabbit femoral condyle deficiency for 3 months. Thus, under high bioactive property and osteoinductivity, and large precision and mechanical strength that can be adjusted, the DLP printed porous β-TCP ceramics is capable of being promising for special uses of bones repairing.