动物体内镁合金的降解和毒性研究

Investigation of magnesium alloy degradation and toxicity in vivo

目的观察动物股骨髁上植入镁合金圆销后,在镁合金降解过程中骨-金属界面的变化及肝肾组织毒性情况。方法在新西兰大白兔股骨髁上横向植入镁合金圆销,术后抗炎处理,自由活动,12周后处死动物取材;X线及microCT观察镁合金圆销大概降解情况以及骨-金属界面情况,组织切片观察肝肾组织结构以判断有无肝肾毒性,血生化检查血中镁离子变化。结果 X线以及CT显示手术结束时镁合金圆销植入位置良好,随着镁合金材料在体内的降解,8周时骨-金属界面首先出现一定空隙,12周时观察到空隙消失,圆销周围未出现骨质吸收溶解。动物体内镁离子各时段变化差异无统计学意义。肝肾组织切片组织形态与正常肝肾组织一致。结论镁合金降解过程中骨-金属界面的变化符合骨质的正常生长状态,且不产生肝肾毒性。

Objective To investigate the mechanism and toxicity of magnesium alloy degradation in vivo. Methods Magnesium sticks were implanted in femurs of New Zealand rabbits. The rabbits were sacrificed at 12 weeks for collection of femurs. X - ray and microCT were used to evaluate the general degradation of the alloy and the structure of implanted bone. Histological observation of liver and kidney were carried out for evaluation of liver and kidney injury. The concentration of the magnesium ion in the blood was also monitored. Results There was a gap observed at bone - alloy border with the degradation of magnesium alloy, but it was slowly disappeared. There was no significant difference in the concentration of the magnesium ion in the blood during the course. No significant pathological change was observed in liver or kidney. Conclusion The bone response at the interface of bone - implant is consistent with normal osteogenesis, pro- viding no magnesium toxicity.