Abstract More and more scientists focus on the growth factors that can improve the bone regeneration. The aim of the study was to prepare a bone scaffolds, and to investigate underlying molecular mechanisms in promoting osteogenesis on the socket of tooth extraction. Chitosan microspheres carrying two osteogenic factors, BMP2 or APN, were prepared by emulsion crosslinking, and then were mixed with ceramic bovine bone to form a novel drug delivery system. To compare the biological activity of the grafts, MC3T3E1 cells were seeded in the scaffold. The influence of the scaffold on cells proliferation and differentiation were investigated. Results show that the average diameter of the chitosan microspheres is 9634 μm. The scaffolds loading BMP2 or APN both contributed to the proliferation of osteoblasts MC3T3E1. Cells seeded in the scaffold loading BMP2 showed higher proliferation. However, cells seeded in the adiponectinloading scaffold showed a higher level in the expression of osteogenesisrelated proteins and genes compared with those in the BMP2 loading scaffold.
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