Huehnerschulte Tim Andreas, Angrisani Nina, Rittershaus Dina, Bormann Dirk, Windhagen Henning, Meyer-Lindenberg Andrea
University of Veterinary Medicine Hannover Foundation, Small Animal Clinic, Buenteweg 9, 30559 Hannover, Germany.
Institute of Materials Science, Hannover Center for Production Technology, University of Hannover, An der Universität 2, 30823 Garbsen, Germany.
Materials (Basel). 2011 Jun 21;4(6):1144-1167. doi: 10.3390/ma4061144.
In magnesium alloys, the components used modify the alloy properties. For magnesium implants in contact with bone, rare earths alloys are commonly examined. These were shown to have a higher corrosion resistance than other alloys and a high mechanical strength, but their exact composition is hard to predict. Therefore a reduction of their content could be favorable. The alloys ZEK100 and AX30 have a reduced content or contain no rare earths at all. The aim of the study was to investigate their in vivo degradation and to assess the suitability of the in vivo µCT for the examination of their corrosion. Implants were inserted in rabbit tibiae. Clinical examinations, X-rays and in vivo µCT scans were done regularly. Afterwards implants were analyzed with REM, electron dispersive X-ray (EDX), weighing and mechanical testing. The in vivo µCT is of great advantage, because it allows a quantification of the corrosion rate and qualitative 3D assessment of the corrosion morphology. The location of the implant has a remarkable effect on the corrosion rate. Due to its mechanical characteristics and its corrosion behavior, ZEK100 was judged to be suitable, while AX30, which displays favorable degradation behavior, has too little mechanical strength for applications in weight bearing bones.
在镁合金中，所使用的成分会改变合金的性能。对于与骨骼接触的镁植入物，稀土合金通常会被研究。这些合金被证明比其他合金具有更高的耐腐蚀性和较高的机械强度，但其确切成分难以预测。因此，减少其含量可能是有利的。ZEK100和AX30合金的稀土含量降低或根本不含稀土。该研究的目的是调查它们在体内的降解情况，并评估体内微计算机断层扫描（µCT）用于检查其腐蚀情况的适用性。将植入物插入兔胫骨中。定期进行临床检查、X射线检查和体内µCT扫描。之后，通过扫描电子显微镜（REM）、能量散射X射线（EDX）、称重和力学测试对植入物进行分析。体内µCT具有很大的优势，因为它可以对腐蚀速率进行量化，并对腐蚀形态进行定性的三维评估。植入物的位置对腐蚀速率有显著影响。由于其机械特性和腐蚀行为，ZEK100被认为是合适的，而AX30虽然表现出良好的降解行为，但对于应用于承重骨来说机械强度过低。
