锶磷灰石生物特性的初步研究

A Fundamental Study on Bioreactions of Sr-HA

目的 :锶磷灰石是一种新型的磷灰石类陶瓷 ,本研究通过动物试验初步探讨其在生物体内的一些特性 ,为临床的广泛应用提供理论基础。方法 :2 4只新西兰大白兔分为 3组 ,双侧下颌角均造成约 6mm× 12mm× 4mm的缺损 ,用不同浓度 (10 % ,5 % ,0 )的锶磷灰石修复 ,术后 1月 ,3月 ,6月时随机处死 1组进行大体观察、X线摄片、组织病理、核素扫描 (发射计算机断层术分析 ) ,评价其生物学性能。结果 :锶磷灰石复合人工骨所致感染和排斥反应均较轻 ,组织切片上反映随材料的降解 ,新生骨大量长入现象比羟磷灰石更为明显 ,且周边软组织内有部分成骨现象 ,X线片上显示随时间的延长 ,材料和骨之间的密合度逐渐增加 ,6月时已几乎融为一体 ,同时锶磷灰石修复侧较羟磷灰石修复侧核素浓聚现象有明显的差异。结论 :锶磷灰石有良好的组织相容性、骨引导性及生物降解性 ,能提高新骨生成量 ,具有更好的骨缺损修复效果 。

Objective: Sr_HA, a new type of hydroxyapatite biomaterial, was implanted into animals to study the bioreaction and character, which would be helpful for the further clinical applications in the future.Methods: Totally 24 rabbits were divided into 3 groups. The bone defect of 6 mm×12 mm×4 mm was made at both mandibular angles of rabbits and Sr_HA of different proportion (10%, 5%, 0) was applied to reform the defects. One group of animals were killed randomly at 1, 3 and 6 months after operation to evaluate the material biological compatibility using anatomic, X_ray examination, histological and ECT methods.Results: The histological photographs showed that Sr_HA caused little infection around implanted area and, almost was not repulsed by hosts. With the degradation of biomaterial, there was more apparent new bone growth in the area around Sr_HA than that around HA and some ossification can be found in soft tissue nearby. Also a tight osteointegrity was gradually got after the operation, according to the results of X_ray and, the border between Sr_HA and bone was hardly discovered at the 6th month after the operation. A more obvious nuclide assembling was observed at the side of Sr_HA by ECT images. With the biodegradation of Sr_HA, more new bone was intruded into the spare space of the biomaterial.Conclusion: Sr_HA has better biocompatibility and higher biodegradation than that of pure HA. It holds an excellent osteoinductivity and fair osteoconductivity to some degree too. So a more satisfying effect of bone defect rehabilitation was gained with the increasing new bone depositing in the free space of the material, when it degraded gradually.\;