许多全关节置换(TJR),通常使用丙烯酸骨水泥(ABC)将植入物粘结在骨中。然而,丙烯酸水泥的工作主要取决于耗时的聚合过程。其放热高的聚合度和未反应的单体释放会导致目标骨骼遭受热和化学坏死,以及聚合过程中水泥的收缩。由于无菌松动,这可能进一步导致关节置换失败。另一方面,放射成像已成为监测手术后愈合过程的有效工具。硫酸钡或二氧化锆由于金属盐和丙烯酸材料之间的不相容性,在大多数市售骨水泥中通常被用作放射线增强剂,金属盐的添加会导致水泥的不均匀性。一些研究表明,这些无机颗粒会导致机械弱点,甚至成为水泥中疲劳裂纹的起始部位。

清华大学医学院生物医学工程系刘静教授团队首次提出将低熔点金属用作骨水泥。 值得注意的是,最早被报道是一种合适的焊料的低共熔合金,其熔化温度低至60℃。 由Bi,In,Sn和Zn组成的低共熔合金已作为无铅焊料提供。在这项工作中,作者发现与常规水泥相比,合金水泥的特点是制备和操作简单,凝固速度快,峰值温度低且射线不透性极佳。

A number of total joint replacements (TJRs), the implant is generally cemented in bone using acrylic bone cement (ABC). However, acrylic cement works mainly depending on the time-consuming polymerization process. Its exothermically high polymerization and unreacted monomer release can cause the target bones to subject to thermal and chemical necrosis, coupled with shrinkage of the cement during polymerization. This may further contribute to the failures in joint replacements due to aseptic loosening. On the other hand, radiological imaging has served as an efficient tool to monitor the healing process after surgery. Barium sulfate or zirconium dioxide is often adopted as radiopacifier in most of the commercial bone cements due to the incompatibility between metal salt and acrylic material, the addition of the metal salt would result in the heterogeneity of cement. Some studies suggest that these inorganic particles can cause mechanical weakness and even become fatigue crack initiation sites in the cement.

DOI: 10.1016/j.biomaterials.2014.08.048

 

李昊宇