国产消旋聚乳酸接骨板体内降解过程观察

Observation of the biodegradation of domestic poly DL lactic acid plates in vivo

目的探讨国产消旋聚乳酸（ＰＤＬＬＡ）接骨板在动物体内的降解过程和影响因素。方法运用国产ＰＤＬＬＡ接骨板行犬下颌骨体部人工骨折内固定，并在股部埋植ＰＤＬＬＡ接骨板作为对照。观察不同时期下颌骨体部骨折区和股部埋植区国产ＰＤＬＬＡ接骨板大体降解情况、骨折愈合情况以及完整的接骨板表面扫描电镜观察结果的变化情况。结果植入前国产ＰＤＬＬＡ接骨板表面光滑，消旋聚乳酸分子间结合紧密；随着时间的推移，植入的ＰＤＬＬＡ接骨板表面降解痕迹逐渐明显，消旋聚乳酸分子间的降解孔隙和密度逐步增大，而且骨折区ＰＤＬＬＡ接骨板的降解速度比股部埋植区更快；骨折愈合情况良好。结论国产ＰＤＬＬＡ接骨板能够在体内逐步自行降解吸收；其降解过程与骨折的愈合过程相吻合。

Objective To analyze the degradation and related factors of domestic poly DL lactic acid(PDLLA) plates in vivo.Methods The artifical transverse fractures in mandibular bodies of dogs were created and internal fixed with domestic PDLLA plates as experimental group,the implanted PDLLA plates in femurs as control.A certain time after the operation,the plates in fractured and implanted regions were collected and undertaken macroscopy and scanning electromicroscopy(SEM),meanwhile the fracture healing status was evaluated. Results With time going on,the surface of domestic PDLLA plates y and density of micro holes among poly DL lactic acid molecules in the PDLLA plates increased gradually.16～20 weeks after operation,the PDLLA plates were absorbed to fragments with fracture healing well. Conclusion Domestic PDLLA plates can be gradually biodegradation in vivo,in which it is correspondent with and accelerative the fracture healing process.