载双磷酸盐骨水泥的静态机械强度和疲劳极限

目的:研究载双磷酸盐骨水泥的疲劳极限和静态机械强度及相关影响因素.方法制备不同载荷的载双磷酸盐纯粉骨水泥试件,根据纯粉载荷及试件的贮存环境进行分组,检测抗压强度、压缩弹性模量、抗张强度、抗弯强度和疲劳极限,威布尔频率函数分析疲劳极限,激光散射法测定双磷酸盐纯粉的粒径.结果:增加纯粉载荷可提高试件的抗压强度极限、抗张强度极限,降低疲劳极限.体液浸泡可降低试件的抗压强度极限、压缩弹性模最、抗张强度极限及疲劳极限.结论:双磷酸盐纯粉的粒径及分布范围较小,载入后丙烯酸骨水泥的静态机械强度高于美国材料实验协会/国际标准化组织标准,但疲劳极限有一定程度下降.与文献报道双磷酸盐的液剂或片剂磨粉相比,纯粉对骨水泥疲劳极限和静念机械强度的影响最小.

Biomechanical strength of bone cement impregnated with diphosphonate

Objective To investigate the biomechanical strength of diphosphonate impregnated bone cement (DIBC). Methods DIBC specimens were manufactured and randomly assigned to the control groups and the DIBC groups. According to the corresponding ASTM/ISO standards, the static biomechanical strength and the fatigue limit were tested systematically. The particle size distribution of diphosphonate powder was analyzed with the laser light scattering method. The fatigue test results, given as number of cycles-to-failure, were analyzed using the linearized format of the two-parameter Weibull function. Results With the drug load increased, there was a slight increase in static biomechanical strength and a moderate decrease in fatigue limit, both with statistical significance. When immersed in PBS before the tests, the DIBC specimens presented an overall significant decrease of static biomechanical strength and fatigue limit. The profile of drug particle sizes presented a normal distribution. Conclusions The adopted diphosphonate is a much homogeneous powder which contains particles with a low range of sizes. The impregnation of diphosphonate exerted no or less negative effect on the biomechanical strength of the acrylic bone cement, of which the static strength of DIBC is maintained high above the ASTM/1SO standards.