Animal implantation with a new type of chitosan microspheres/calcium phosphate cement / 北京大学学报(医学版)

ABSTRACT

Objective:To investigate bioactivity,biodegradation,bone conductive properties,and clinical maneuverability of a novel injectable chitosan microspheres/ calcium phosphate cement(CPC).Methods: The bone defect of ??4 mm?4 mm?6 mm was made at both thighbones of 12 rabbits,and experimental material(chitosan microspheres/CPC) or control material(?-tricalcium phosphate cement,?-TCP) was injected into the defect respectively.The filling situation was evaluated by X-ray 3 days after operation.The rabbits were divided into three groups,four for each group.The samples with chitosan microspheres and the control with ?-TCP were collected at 8,16,24 weeks after operation.Histological examination and scanning electron microscope(SEM) evaluation were performed.Results: The absorption of implants with chitosan microspheres was observed at 8 weeks,and became more apparent at 16 weeks.Different size of cavities were observed in CPC after the degradation of chitosan microspheres.The chitosan microspheres/CPC was dramatically degradated after 24 weeks with a few chitosan microspheres,and new bone replaced the degradated materials.The implants with ?-TCP were absorbed slowly compared with the chitosan microspheres/CPC.The cavities in ?-TCP were small.Conclusion: The chitosan microspheres/calcium phosphate cement has the characters of good biocomptable and osteocombinative ability.Compared with the control material,adding chitosan microspheres into CPC could enhance its degradability and facilitate the new bone formation.