Mandrino A, Moyen B, Ben Abdallah A, Treheux D, Orange D
Pavillon I, Hôpital Edouard Herriot, Lyon, France.
Biomaterials. 1990 Jul;11:88-91.
Three base alumina ceramics with dispersoids: monoclinic zirconia alumina (A5Z), tetragonal zirconia alumina (A20Z) and aluminalon (Aa20) have been investigated because of their improved mechanical properties with reference to pure alumina (AI203). Bending strength and fracture toughness are twice higher than alumina for the most toughened. These two parameters were measured by four-points bending tests after 1 week, 1, 2, 3, 6, 12 months of non loaded in vivo aging in wistar rats. They showed a little decrease for AI203 and Aa20 and a total stability for A5Z and A20Z even after one year. For tribologic study of the ceramic/polyethylene combination, cylinder against plane and pin on flat tests were conducted on an alternative movement with hip parameters of speed and load in presence of ringer solution. For the most representative test (pin on disk), the friction coefficients were nearly the same for all materials but UHMWPE wear volume was twice lower against A20Z than against AI203. A20Z/UHMWPE combination would be very interesting as new friction couple for total hip arthroplasty. Further studies are currently conducted.
单斜氧化锆氧化铝（A5Z）、四方氧化锆氧化铝（A20Z）和铝基氮化硅（Aa20）因其相对于纯氧化铝（AI203）而言有所改善的机械性能而受到研究。对于增韧效果最佳的材料，其弯曲强度和断裂韧性比氧化铝高出两倍。在Wistar大鼠体内进行1周、1、2、3、6、12个月的无负荷老化后，通过四点弯曲试验测量这两个参数。结果显示，即使在一年后，AI203和Aa20的这两个参数略有下降，而A5Z和A20Z则完全稳定。对于陶瓷/聚乙烯组合的摩擦学研究，在林格氏溶液存在的情况下，以髋关节的速度和负荷参数进行交替运动，进行圆柱对平面和销对平面试验。对于最具代表性的试验（销对盘），所有材料的摩擦系数几乎相同，但超高分子量聚乙烯（UHMWPE）相对于A20Z的磨损量比对AI203时低两倍。A20Z/UHMWPE组合作为全髋关节置换术的新型摩擦副将非常有意义。目前正在进行进一步的研究。
