双相陶瓷样生物骨修复骨缺损

Repairing the bone defects with biphasic ceramic-like biologic bone

背景:已有研究表明课题组制备的双相陶瓷样生物骨符合骨组织工程支架或直接作为植骨材料的要求。实验将材料植入兔桡骨节段性骨缺损,以进一步了解双相陶瓷样生物骨修复骨缺损的能力。目的:用双相陶瓷样生物骨来修复兔桡骨骨缺损,评价双相陶瓷样生物骨的成骨作用。设计、时间及地点:随机对照动物实验,于2008-03/09在昆明医学院动物实验中心完成。材料:将猪椎骨煮沸12h,经系列乙醇脱水后于800℃条件下煅烧6h后制得陶瓷化骨,完全去除有机成分,再将陶瓷化骨与适当浓度的焦磷酸钠溶液复合后于800℃煅烧1h,经缓慢冷却后制得双相陶瓷样生物骨。方法:成年日本大耳白兔36只随机分为3组:双相陶瓷样生物骨组、自体髂骨组、空白对照组,每组12只。在兔双侧桡骨造成1.0cm骨缺损后分别植入双相陶瓷样生物骨材料、自体髂骨,空白对照组不做任何处理直接缝合切口。主要观察指标:术后4,8,12,24周取出双侧尺、桡骨后摄X射线片,了解移植物的X射线变化情况。制备组织切片,光镜下观察移植物的组织形态特征及新骨形成情况。结果:X射线片:双相陶瓷样生物骨组在术后4周可见材料密度较宿主骨高,与宿主骨分界清楚,8周后材料与宿主骨分界模糊,12周后大部分材料呈高密度影,24周后材料仍有部分高密度影。自体髂骨组在术后4周可见髂骨与宿主骨分界模糊,24周后植骨部位密度与宿主骨一致。组织学形态观察:双相陶瓷样生物骨组发现有新骨贴附材料生长,材料随着时间的推移逐渐降解吸收,新骨形成增多。24周后新骨形成明显增多,仍可见部分残余材料;自体髂骨组在12周后髓腔完全再通,24周后植骨部位与宿主骨结构没有差别;空白对照组未见骨连接或髓腔再通,随着时间的推移缺损两端逐渐封闭并硬化。结论:实验初步表明双相陶瓷样生物骨可用于桡骨骨缺损的修复。

BACKGROUND： Biphasic ceramic-like biologic bone which is satisfied by bone tissue-engineering scaffold or bone transplantation has been reported yet. While, biphasic ceramic-like biologic bone in this study was transplanted into radial bone defect segment of rabbits so as to further study its repairing ability. OBJECTIVE： To evaluate the osteogenesis of biphasic ceramic-like biologic bone in repairing bone defects. DESIGN, TIME AND SEI-FING： A randomized controlled animal experiment was performed at Animal Experimental Center of Kunming Medical College from March to September 2008. MATERIALS： The porcine vertebral bone was boiled for 12 hours, after a series alcohol dehydration, the bone was calcined for 6 hours at 800℃ to remove organic matrix and obtain ceramic bone; thereafter, the ceramic bone was soaked in Na4P2O7.10H2O and calcined at 800 ℃ for 1 hour. The material was cooled at room temperature and harvested biphasic ceramic-like biologic bone. METHODS： A total of 36 adult Japanese rabbits were randomly divided into 3 groups： biphasic ceramic-like biologic bone group, autogenous lilac bone group, and blank control group, with 12 rabbits for each group. 1.0-cm bone defects were made on both radiuses of rabbits, which were repaired with biphasic ceramic-like biologic bone and autogenous lilac bone. Rabbits in the blank control group were not treated with any methods. MAIN OUTCOME MEASURES： The specimens of bilateral ulnar and radial bones were examined after 4, 8, 12, and 24 weeks using X-ray, and the tissue form and new bone formation of grafts were observed under optic microscopy. RESULTS： X-ray： Density of biphasic ceramic-like biologic bone was higher than host bone 4 weeks postoperatively. The border was clear after 4 weeks and blurred after 8 weeks. There were mostly high-density images in biphasic ceramic-like biologic bone group after 12 weeks, and partially high-density images after 24 weeks. The border between autogenous iliac bone and host bone was blurred after 4 weeks, and there was no difference in density between autogenous lilac bone and host bone after 24 weeks. Histological examination： New bone grew and attached the surface of biphasic ceramic-like biologic bone. With a prolonged transplantation time, biphasic ceramic-like biologic bone was gradually degraded and absorbed, while more and more new bones formed. After 24 weeks, new bone formation was obviously increased, and there was still some remnant biphasic ceramic-like biologic bone. Medullary cavity of bone was formed in the autogenous lilac bone group after 12 weeks, and there was no difference in structure between autogenous lilac bone and host bone after 24 weeks. Bone connection or formation of medullary cavity was not observed in the blank control group. With a prolonged time, both ends of defects were gradually closed and became sclerosis. CONCLUSION： Biphasic ceramic-like biologic bone can repair radial bone defects.