Reparation of bone defect by poriferous ?-tricalcium phosphate graft / 解放军医学杂志

ABSTRACT

Objective To prepare poriferous ?-tricalcium phosphate(?-TCP) particles and investigate the possibility of these particles to serve as bone graft and bone tissue engineering scaffold.Methods Poriferous anorganic bone particles were prepared with healthy bovine cancellous bone by removal of cells,defat and double calcination,finally with ?-TCP remained as the main ingredient.A bone defect was made in rabbit's femur,and it was repaired with poriferous ?-TCP bone graft.The results were observed by X-ray,molybdenum target films,fluorescence label and histology at the 4th,8th and 12th week after operation.Results The nature of cancellous bone structure was still maintained in the poriferous ?-TCP bone graft,even retaining its contour after it was transplanted in the bone defect.At the 4th week after operation,the graft was integrated with neighboring tissues,and the new bone gradually grew in the ?-TCP bone graft pores,with delineation of bone defect remaining clear.There was no obvious absorption of the graft,neither growth of soft tissues or bone tissue into the central part.At the 8th week after operation,the soft tissue further grew into the inside of the ?-TCP bone graft,and little bone tissue grew in the central part.At the 12th week after operation,the graft was firmly surrounded with new bone tissue,the demarcation between the graft and new bone becoming obscure,and the graft was partially absorbed,with thickening of bone trabeculae,which extended into the center of ?-TCP bone.However,the speed and quantity of the new bone formation were deteriorated.Histologic examination also found that the ?-TCP bone graft degenerated slowly with passage of time.Conclusion The poriferous ?-TCP bone graft possesses excellent osteogenesis for repairing a bone defect,and may be used as bone tissue engineering scaffold,though its degradation speed should be ameliorated.