Osteogenesis study of compound antitumor coral hydroxyapatite in vivo / 中国组织工程研究

ABSTRACT

BACKGROUND: Compound antitumor coral hydroxyapatite (CCHA) has a good delayed-release and anti-tumor effect. However, whether the high-dose drug contained in the CCHA influences normal induction, conduction and growth of bone tissues at the implant site is unclear.OBJECTIVE: To establish an osteogenesis model of CCHA and to investigate the osteogensis effect and rule of self-made CCHA in vivo. METHODS: Implants of CCHA (20%CDDP-CHA w/w) and CHA(control, 0% CDDP w/w) were implanted into the metaphyseal holes of rabbit femur. X-rays and decalcified histological section of rabbit femoral bone with hematoxylin and eosin staining were used regularly to investigate the degradation of CCHA and CHA, and how bone tissues grow at the implant site. RESULTS AND CONCLUSION: After implantation, CHA crystals were faster than CCHA in connecting with surrounding bone tissues and forming bone bridges. The borderlines of implanted CHA became obscure in 4 weeks. Loose connective tissues were found in pores of the CHA and osteoblasts were growing on the surface. Bone tissues of the surrounding gradually grew into the CHA, finally repaired the bone defects. At the beginning of implantation, CCHA mainly inhibited the growth of surrounding tissues until 6-12 weeks later, normal bone tissues gradually grew into pores of CCHAs, and healed bone defects at 26 weeks. CCHA can inhibit the osteogenesis effects at early stage; however, it can achieve bone healing with surrounding bone defect ultimately.