羟基磷灰石/超高分子聚乙烯复合材料的组织相容性及骨传导性实验研究

目的　旨在证实羟基磷灰石 超高分子聚乙烯 (hydroxyapatite ultra highmolecularweightpolyethtlene ,HA UHMWPE)复合物具有HA的良好生物性能和骨传导性 ,又保留有超高分子聚乙烯的可塑性。方法　分别对 2 4只新西兰白兔行HA、HA UHMWPE、UHMWPE材料眶上缘置入 ,于术后 1、4、8、12周行大体、光镜组织学和电镜检查。结果　置入物无脱出、移位。组织学检查显示 ,HA组植入物在术后 1周即有新生血管长入和成纤维细胞活跃增殖 ,在术后 8周时可见骨细胞 ,术后 12周可见钙盐呈板状骨样沉积。而在HA UHMWPE组中材料的边缘反应同HA组。UHMWPE组在术后 1周有薄层纤维结缔组织包裹。电镜检查 ,在HA及HA UHMWPE组未见骨细胞 ,UHMWPE组见其包膜胶原纤维排列清晰。结论　HA UHMWPE复合物具有HA的良好生物活性及骨传导性 ,因此此复合物有望成为一种较理想的骨替代材料 ,尤其是眶骨整复的替代材料。

Experimental study of the biocompatible and osteoinductive behavior of the hydroxyapatite/ultra-high molecular weight polyethtlene composite

OBJECTIVE: To compare the biocompatibility and osteoinductive behavior of HA (hydroxyapatite) and HA/UHMWPE (ultra-high molecular weight polyethtlene) composite in orbital implantation. METHODS: Osteoectomy of the upper orbital rim was perform on 24 adult New Zealand rabbits. The animals were randomly divided into 4 groups with 6 of each. The HA, HA/UHMWPE composite or UHMWPE (10 mm x 10 mm x 3 mm in size) was implanted to the upper orbital defect of the animal in respective group. Animals were sacrificed at 1, 4, 8, 12 weeks. Histopathologic sections of the implants were evaluated and compared with light and transmission electron microscopy study. RESULTS: During the experimental period of 12 weeks, there was no implant extrusion or displacement. In the groups of HA and HA/UHMWPE composite, vascular ingrowth and fibroblasts were observed shortly and osteocytes were seen at 8 weeks. Calcium deposition of the implants showed a laminar fashion at 12 weeks. In the group of UHMWPE, fibrous membranes were seen around the implant at 1 week. Transmission electron microscopy study showed that in the HA and HA/UHMWPE groups, fibroblasts and vascular ingrowth could be seen, but osteocytes were not observed. CONCLUSION: HA/UHMWPE composite demonstrated biocompatibility and osteoinductive property. It would be a good substitute for bone, particularly for orbital bone.