泡沫碳化硅细胞相容性及动物体内植入实验研究

Study on Cytocompatability and Animal Implantation Test of Foam SiC

采用高分子热解结合可控熔渗反应烧结方法制备泡沫SiC,观察体外接种到泡沫SiC表面的成骨细胞MG63的贴壁和生长状况,评价泡沫SiC的细胞相容性.通过建立兔下颌临界骨缺损人工材料植入模型,进行大体标本观察、组织学观察及图像分析,探讨了泡沫SiC作为骨替代材料的可行性.研究结果表明,体外成骨细胞MG63在泡沫SiC表面的生长状态良好.体内植入实验的26只实验动物健康状况良好,伤口均为一期愈合.大体标本观察表明,各时间点内的泡沫SiC周边及其内部网孔内均有不同程度的骨组织形成;组织学观察可见骨组织的修复属于正常的骨修复过程.植入4w后,泡沫SiC内新生骨的四环素荧光标记率和成骨面积均低于HA,而在8w及24w后与HA接近,其差异无统计学意义.由此表明泡沫SiC具有良好的细胞相容性,且泡沫SiC修复兔下颌骨缺损的远期效果与HA相似,具有较好的骨传导性.

Foam SiC was prepared by macromolecule pyrogenation combined with reaction bonding method.The osteoblast-like cells MG63 were seeded and cultured in vitro on the foam SiC and observed under both SEM and TEM to further evaluate the cytocompatability of this novel material.The feasibility of the foam SiC as a bone replacement material for clinical treatment was also studied by establishing an animal model for repairing mandibular critical-sized defects in rabbits,and by using general observation,histological observation and bone histomorphometry.The results show that MG63 cells attach and grow well on the surface of the foam SiC,which indicates that the foam SiC is non-toxic and possesses good cytocompatibility.The 26 tested rabbits are all in healthy conditions and the wounds are healed completely.The different degree of osteogenesis is observed on both periphery and inner mesh of the foam SiC at each time point,and the foam SiC shows no adverse effect to the process of bone repair.It is found that both the rate of tetracycline fluorescence labeling and the new bone area on the foam SiC are lower than those of hydroxyapatite（HA） after 4w implantation,but there are no statistical differences after both 8w and 24w implantations,indicating that the foam SiC should be similar to HA in osteo-conduction ability judging from the long-term repair effect to mandibular defects.