Preparation And Characterization Of A Novel Self-setting Bone Substitute Containing Of RhBMP-2 Loaded Microspheres

The repairing of bone defect is one of the problems in orthopedics, which has not been solved satisfactorily today. Traditional methods such as autograft and allograft have some disadvantages that are hard to deal with. People have been searching for the ideal bone substitutes. As alternatives to autografts and allografts various kinds of synthetic products have been developed and used as bone substitutes. Of all materials available, calcium phosphate cement (CPC) has received considerable attention. CPC consists of a mixture of fine particles of calcium phosphate salts, the CPC powder can be mixed with water to form a paste that can conform to osseous defects and set in vivo to form degradable hydroxyapatite with a high level of biocompatibility and osteoconductivity. So CPC is highly promising for a bone substitute in orthopedic and served as carrier materials for growth factors such as BMP. However, the lack of macropores and low porosity make its resorb rate rather slow. Meanwhile, when the CPC was used as the carrier of BMP, the BMP release rate is rather slow. It's clinical applications may thus be limited.In the present study we synthesized a novel bone substitute by incorporating rhBMP-2 loaded poly (lactide-co-glycolide) microspheres into calcium phosphate...