Schreiner U, Koester H, Pott P, Scheller G, Schwarz M
Orthopädisch-Unfallchirurgisches Zentrum, Universitätsklinik Mannheim.
Z Orthop Unfall. 2009 Sep-Oct;147(5):603-9. doi: 10.1055/s-0029-1185623.
The aim of this study was to analyse mechanically and histologically the osteointegration of porous-surfaced ceramic implants made of an alumina matrix composite (AMC) by assessing maximum shear strength and histomorphometric bone ongrowth.
The surfaces of the cylindrically shaped AMC test implants were characterised by a porosity of 40% and a pore size of 150 to 300 microm. A total of 24 test cylinders was implanted bilaterally into the femurs of 6 female adult Goettinger minipigs. 12 weeks after surgery the animals were sacrificed. 12 test implants were used for a push-out test and 12 test implants were evaluated histologically.
The mean maximum shear strength of the bone-implant interface was 7.6 +/- 2.0 MPa. Direct bone attachment was found in 7.4 +/- 3.4% of the histologically analysed surfaces.
In summary, porous-surfaced AMC test implants demonstrated good mechanical stability in spite of a low percentage of bone ongrowth. This discrepancy could potentially be explained by bone ingrowth into the pores and subsequent interlocking mechanisms.
本研究的目的是通过评估最大剪切强度和组织形态计量学的骨长入情况，对由氧化铝基复合材料（AMC）制成的多孔表面陶瓷植入物进行力学和组织学分析。
圆柱形AMC测试植入物的表面孔隙率为40%，孔径为150至300微米。总共24个测试圆柱体双侧植入6只成年雌性哥廷根小型猪的股骨中。术后12周处死动物。12个测试植入物用于推出试验，12个测试植入物进行组织学评估。
骨-植入物界面的平均最大剪切强度为7.6±2.0兆帕。在组织学分析的表面中，7.4±3.4%发现有直接骨附着。
总之，尽管骨长入百分比低，但多孔表面的AMC测试植入物表现出良好的力学稳定性。这种差异可能是由于骨长入孔隙并随后形成互锁机制所致。
