Gartzke Ann-Kathrin, Julmi Stefan, Klose Christian, Besdo Silke, Waselau Anja-Christina, Meyer-Lindenberg Andrea, Maier Hans Jürgen, Wriggers Peter
Institute of Continuum Mechanics, Leibniz University Hannover, Appelstraße 11, 30167, Hannover, Germany.
Institut für Werkstoffkunde (Materials Science), Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany.
J Mech Behav Biomed Mater. 2020 Sep;109:103825. doi: 10.1016/j.jmbbm.2020.103825. Epub 2020 Apr 28.
Degradable bone substitutes made of magnesium alloys are an alternative to biological bone grafts. The main advantage is that they can be manufactured location- and patient-specific. To develop and scale appropriate implants using computational models, knowledge about the mechanical properties and especially the change in the properties during the degradation process is essential. Therefore, degraded open-pored implants were investigated using scanning electron microscope and nanoindentation to find their material composition and mechanical properties. Using both techniques the correlation of the material composition and the average modulus was determined. It could be shown that the average modulus of the degradation layer is distinctly lower than that of the base material. The local average modulus of degrading implant highly depends on the magnesium concentration and the accumulation of elements from the environment. A decrease in magnesium concentration leads to a decrease in the average modulus. Thus, the degrading implant had a lower stiffness than the initial structure.
由镁合金制成的可降解骨替代物是生物骨移植的一种替代方案。其主要优点在于能够根据具体位置和患者定制生产。要利用计算模型开发并扩大合适的植入物规模，了解其力学性能，尤其是降解过程中的性能变化至关重要。因此，使用扫描电子显微镜和纳米压痕技术对降解的开孔植入物进行了研究，以确定其材料成分和力学性能。通过这两种技术确定了材料成分与平均模量之间的相关性。结果表明，降解层的平均模量明显低于基材。降解植入物的局部平均模量高度依赖于镁浓度以及环境中元素的积累。镁浓度降低会导致平均模量下降。因此，降解后的植入物刚度低于初始结构。
