Osteogenetic and mechanical property studies of reinforced self-hardening calcium phosphate cement with collagen scaffold / 中国矫形外科杂志

ABSTRACT

[Objective]To examine whether collagen scaffold(CS) would strengthen calcium phosphate cement(CPC) in vitro,and to investigate whether CPC enhanced with CS would accelerate the osteogenesis for repairing bone defect in rabbits.[Method] A standard 3-piont flexural test was used to fracture the set specimens and to measure the flexural strength,work-of-fracture(WOF) and elastic modulus of CPC and cpclcs.Both cements were implanted into cylinder cavities drilled in 20 rabbit femoral condyles.After 22 and 54 weeks of implantation,histological observations were performed.[Result]The CS had significant effects on composite of mechanical properties.The CPC/CS had a flexural strength 64.2% higher,WOF 3 933.3% higher,and elastic modulus 45.7% lower than the CPC without CS.At 22 weeks,histological study showed collagen fibers of the CPC/CS composite were entirely resorbed and new bone was formed instead.With unreinforced CPC,there were a little bone formation and biodegradation of cement on the margin but not in the interior of CPC.At 54 weeks,plentiful growing bone and bone marrow-like tissue fully filled in pores created by biodegradation of CPC/CS.Although bone formation and biodegradation of cement were more obvious on the margin of CPC cylinder at 54 weeks than 22 weeks,new bone did not present in the interior of CPC yet.[Conclusion]Collagen scaffold not only reinforces CPC,but also accelerates bone formation in the interior of CPC/CS composite.Therefore,CPC/CS could be novel biomaterial as an endosteal implant.