Clinical Application of High Strength poly (L-Lactide) with Osteoductivity

我们近年来开发的超高强度聚l -丙交酯骨植入物（棒、螺钉）被证实是安全的，其长期的组织学组织反应也得到了澄清。在体内研究了一种表面包覆aw -玻璃陶瓷的新型聚l -丙交酯生物活性复合材料。植入兔胫骨后，随时间处死动物，并进行分离试验。分离测试值很低，在0 ~ 300克之间，分离发生在聚l -丙交酯和aw -玻璃陶瓷的界面（涂层）上。聚l -丙交酯的降解在植入后18和24个月延迟。本研究表明，涂层是聚l -丙交酯与aw -玻璃陶瓷复合材料的最关键的周点。认为除非用不同的方法将这两种材料重新制造成稳定的结构，否则这种高贵的材料不能用于临床。我们还在兔骨缺损模型上进行了另一项实验，使用拉伸的聚l -丙交酯薄膜和压电。按4:1拉伸的聚l -丙交酯膜的骨导电性明显优于未拉伸的膜。将1:1拉伸的聚l -丙交酯薄膜与对照聚乙烯薄膜进行比较，前者具有较大的骨体积。在未来，绘制的聚l -丙交酯膜可以作为骨缺损修复的模型，与骨诱导因子如BMP联合使用。

Ultra high strength poly (L-lactide) osteosynthetic implants (rods and screws) which we have developed in recent years was confirmed to be safety and its long-term histological tissue reaction has also been clarified. A new bioactive composite made of poly (L-lactide) with AW-glass ceramic coated on its surface was studied in vivo. After implantation into the rabbit tibiae, animals were sacrificed with time and a detaching test was performed. The values of detaching tests was very low, ranging from zero to 300 grams, and separation occurred in the interface (coating layr) between poly (L-lactide) and AW-glass ceramic. The degradation of poly (L-lactide) delayd at 18 and 24 months after implantation. From this study, it has been demonstrated that the coating layr was the most critical week point on the new bioactive composite made of poly (L-lactide) with AW-glass ceramic. It is considered that this noble material cannot be used clinically unless both materials are re-manufactured into a stable structure with some different methods.We also performed another experiments using drawn poly (L-lactide) films with piezo-electricity in a rabbit bone defect model. Drawn poly (L-lactide) films by 4 : 1 showed a significantly better osteoconductivity that that of undrawn ones. Drawn poly (L-lactide) films by 4 : 1 and polyethylene films as a control were compared, and the former had a much bone volume. In the future, drawn poly (L-lactide) films can be used as a model for repair of bone defect in combination with osteoinductive factors such as BMP.