Kitsugi T, Yamamuro T, Takeuchi H, Ono M
Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Japan.
Clin Orthop Relat Res. 1988 Sep(234):280-90.
The present study suggests that bonding does not vary in hydroxyapatite (HA) with different sintering temperatures implanted in bone tissue. The apparent unimportance of strict temperature regulation greatly simplifies HA processing. Three samples of HA (15 mm x 10 mm x 2 mm, abraded with 2000 alumina powder), of which sintering temperatures and microporosity were 800 degrees (45%), 1000 degrees (4.8%), and 1200 degrees (0.4%), respectively, were prepared. They were implanted into the metaphysis of tibia of mature male rabbits. Segments of the tibia containing the HA were excised and prepared for the detaching test. The failure load, when an implant detached from the bone or the bone broke, was then measured. Failure loads in HA (800 degrees), HA (1000 degrees), and HA (1200 degrees) ten weeks after implantation did not differ. Those in HA (800 degrees), HA (1000 degrees), and HA (1200 degrees) 25 weeks after implantation were 2.58 +/- 1.88 kg, 6.46 +/- 1.43 kg, and 6.50 +/- 2.71 kg, respectively. The failure load in HA (800 degrees) versus HA (1200 degrees) and that in HA (800 degrees) versus HA (1000 degrees) differed significantly (p less than 0.05). The lower failure load of HA (800 degrees) 25 weeks after implantation can be explained by its weakened mechanical strength due to high porosity. Bonding between bone tissue and three types of HA did not vary as observed by contact microradiography, Giemsa surface staining, and scanning electron microanalyzer-energy dispersive X-ray microanalyzer.
本研究表明，植入骨组织中不同烧结温度的羟基磷灰石（HA）的结合情况并无差异。严格温度调节看似并不重要，这极大地简化了HA的加工过程。制备了三个HA样本（15毫米×10毫米×2毫米，用2000目氧化铝粉末研磨），其烧结温度和微孔率分别为800摄氏度（45%）、1000摄氏度（4.8%）和1200摄氏度（0.4%）。将它们植入成年雄性兔胫骨的干骺端。切除包含HA的胫骨段并准备进行分离试验。然后测量植入物从骨中分离或骨断裂时的破坏载荷。植入后10周，HA（800摄氏度）、HA（1000摄氏度）和HA（1200摄氏度）的破坏载荷没有差异。植入后25周，HA（800摄氏度）、HA（1000摄氏度）和HA（1200摄氏度）的破坏载荷分别为2.58±1.88千克、6.46±1.43千克和6.50±2.71千克。HA（800摄氏度）与HA（1200摄氏度）以及HA（800摄氏度）与HA（1000摄氏度）之间的破坏载荷差异显著（p小于0.05）。植入后25周HA（800摄氏度）较低的破坏载荷可归因于其因高孔隙率而减弱的机械强度。通过接触微放射摄影、吉姆萨表面染色和扫描电子显微镜 - 能量色散X射线微分析仪观察发现，骨组织与三种类型的HA之间的结合没有差异。
