Biocompatibility and degradation of an injectable nano-sized composite bone substitute / 第二军医大学学报

ABSTRACT

Objective:To evaluate the in vitro cytotoxicity,in vivo response and degradation of a new injectable nano-hydroxyapatite(n-HA)/calcium sulphate hemihydrate(CSH) bone substitute in rabbits and to discuss its possible bio-degeneration mechanism.Methods: Pure CSH,n-HA,10%n-HA+CSH,20%n-HA+CSH,and 40%n-HA+CSH(the last 3 containing 10%,20%,and 40% n-HA,respectively) were subjected to MTT assay for their in vitro cytotoxicities.20%n-HA+CSH was implanted into rabbits' muscle and bone defects in the right femur,and the general conditions of rabbits,the pathological and TEM manifestations of tissues,and the imaging alterations were all observed 5 days,2,3,4,6,8,and 12 weeks after implantation.Results: Test of cytotoxicity showed that the average cell proliferation rate was over 77% after treated with the solutions of 5 bone substitutes(P