聚氨酯/纳米羟基磷灰石+聚酰胺66一体化复合支架材料修复软骨及软骨下骨缺

背景:目前软骨支架材料种类繁多,随着制备工艺、结构及表面改性技术的提高,材料的性能更加完善,而一体化修复关节软骨及软骨下骨缺损对于软骨替代材料的稳定性十分重要.目的:观察新型生物复合材料聚氨酯/纳米羟基磷灰石+聚酰胺66一体化修复关节软骨及软骨下骨缺损的效果.方法:将多孔聚氨酯,纳米羟基磷灰石+聚酰胺66、致密聚氨酯,纳米羟基磷灰石+聚酰胺66及单纯纳米羟基磷灰石+聚酰胺66材料植入狗膝关节,空白组作为对照,分别于4,12,24周,对动物行大体观察,局部行组织学切片观察,对支架材料植入后24周修复组织进行组织学评分,扫描电镜观察生物材料与周边软骨连接界面的情况.结果与结论:支架材料植入后12,24周,下层材料中可见有骨组织长入,多孔聚氨酯与周边软骨融合较好,周边软骨未见明显退变.植入后24周,扫描电镜见上层材料多孔聚氨酯与周围正常软骨结合牢固,未见明显间隙,周围软骨未见明显退变;致密聚氨酯与周边正常软骨有较明显间隙,周边正常软骨退行性改变,变薄、卷曲.说明新型多孔聚氨酯/纳米羟基磷灰石+聚酰胺66支架材料在结构上更加接近正常软骨及软骨下骨,对软骨及软骨下骨缺损的修复效果更加显著.

Repairing articular cartilage and subchondral bone defects with polyurethane/nano-hydroxyapatite+polyamide66 composite

BACKGROUND: Cartilage stent materials were abundant. With the development of preparation technique, structure, and surface modification technique, performance of materials were improved remarkably; thus, Integrated-repaidng defects of articular cartilage and subchondral bone required high stability of cartilage replacement materials.OBJECTIVE: To evaluate the effect of polyurethane/nano-hydroxyapatite+polyamide66 (PU/n-HA+PA66) biological composite material on repairing articular cartilage and subchondral bone.METHODS: Twenty dog models were randomly divided into 4 groups: porous PU/n-HA+PA66 implant group, compact PU/n-HA+PA66 implant group, n-HA+PA66 implant group and blank control group. The macroscopic and histological evaluations were performed at 4, 12, and 24 weeks postoperatively. The interfaces of biomaterial implants with articular cartilage were observed by scanning electron microscope.RESULTS AND CONCLUSION: After 12 and 24 weeks, bone tissue grew into lower layer materials. Porous PU was well fused with peripheral cartilage. At 24 weeks postoperatively, the porous PU was closely connected with surrounding articular cartilage than the compact PU, and the articular cartilage surrounding the compact PU degenerated obviously. PU/n-HA+PA66 had a similar structure with normal cartilage and subchondral bone and had remarkable effects on repairing defects of articular cartilage and subchondral bone.