小动物实验用镁锰合金颈椎植入物制备及其可行性研究

Development and feasibility of Mg-Mn alloy cervical implant for small animal experiments

目的应用镁锰合金材料制备用于小动物实验的颈椎植入物,验证表面处理对合金抗腐蚀能力的改进,并分析其用于小动物实验的可行性。方法根据新西兰兔颈椎解剖设计镁锰合金(Mg-1.3Mn)颈椎植入物,应用微弧氧化方法在镁合金表面制备含硅生物活性涂层。体外使用人工组织液浸泡,观察降解情况。体内实验将经表面处理的镁锰合金植入物及同尺寸未经表面处理的镁锰合金植入物、钛合金植入物植入兔颈椎椎体,观察不同时间植入物的体内降解情况。结果镁锰合金颈椎植入物制备成功,表面改性后其抗腐蚀性能明显提高,经手术成功固定于兔颈椎椎体上,与未经表面改性的镁锰合金植入物相比,体内、体外的降解速度均显著降低,扫描电镜及能谱分析等结果表明表面改性的镁锰合金抗腐蚀性有较大改善。结论镁锰合金颈椎植入物可用于小动物颈椎部位实验,适当的表面处理能够有效改进合金的抗腐蚀性能。

Objectives To verify the improvement of corrosion resistant ability after surface modification and its feasibility for small animal experiment of a newly developed magnesium-manganese （Mg-Mn） alloy cervical implants. Methods A new kind of Mg-Mn alloy （Mg-1.3Mn） cervical implants were designed according to the anatomy features of New Zealand rabbit. Micro arc oxidation （MaO） was used for the implants＇ surface modification, in order to prepare the silicious bioactive coating. The corrosion in vitro was observed by immersing implants into artificial tissue fluid. Then the implants with and without surface modification were implanted in the cervical vertebrae of the New Zealand rabbit by surgery. The corrosion of the implants at different time was observed by scanning electron microscope （SEM）. Results The Mg-Mn alloy implants were successfully developed and their electrochemical properties were notably improved after surface modification. Implants were fixed to the rabbit＇ s vertebral bodies. The corrosion rate of the implants with surface modification, compared with those without, was significantly slowed down both in vivo and in vitro, and the corrosion resistant ability was obviously improved, proved by SEM and EDX, etc. Conclusion Mg-Mn alloy cervical implants can be used in small animal experiments and proper surface modification can improve the alloy＇ s corrosion resistant ability effectively.