纳米羟基磷灰石修复兔颌骨缺损的组织学分析

背景:纳米材料修复骨缺损的临床应用组织相容性、生长特性、生物降解性及修复机制需进一步研究. 目的:观察纳米羟基磷灰石修复颌骨缺损模型兔的生长特性及生物相容性.设计:随机分组动物实验.单位:北京积水潭医院,佳木斯大学口腔医学院.材料: 选用24只新西兰白兔,雌雄不拘, 体质量2.5～3.5 kg,由佳木斯大学动物实验中心提供.实验处置过程符合动物伦理标准.Nano-HA由佳木斯大学材料工程学院提供,常规高温高压消毒备用.普通HA购自武汉工业大学,粒径为1.0～2.0 μm.方法:实验于2001-11/2006-05在佳木斯大学实验动物中心完成.摸球法将实验兔随机分为实验组和对照组,每组12只.各组实验兔在下颌骨体部造成直径1.5 cm的骨缺损,实验组以纳米羟基磷灰石修复,对照组以普通羟基磷灰石修复,于术后1,4,8,12周分别麻醉后处死,用医学图像分析系统分析各组分的组织生成量,并进行组织学定性和定量分析,观察材料的组织相容性及新生骨生成情况.主要观察指标:材料的组织相容性及新生骨生成情况.结果:实验组骨缺损修复区随时间增长修复材料被利用与新生组织结合成骨而不断减少,直至与正常骨接近而趋于稳定,对照组骨痂不能长入材料内.相关分析结果表明材料与新生骨之间呈直线负相关(r =-0.912 0,P < 0.01).骨缺损的修复过程中新生骨与纳米羟基磷灰石之间相互关系密切,且随着新生骨不断产生、增多,修复材料被利用与新生组织结合成骨而不断减少.结论:纳米羟基磷灰石可与新生骨组织结合且成骨较快,有良好的生物相容性.

Histological analysis of nano-hydroxyapatite for repairing defect in rabbit jaw

BACKGROUND: To repair bone defect, histocompatibility, growing characteristics, biodegradation and repairing mechanism of nanometer need to be further studied in clinic. OBJECTIVE: To observe the growing characteristics and histocompatibility of nano-hydroxyapatite (Nano-HA) for repairing jaw defect of rabbits.DESIGN: Randomized grouping animal study.SETTING: Beijing Jishuitan Hospital and Stomatology College of Jiamusi University.MATERIALS: A total of 24 New Zealand rabbits, either gender, weighing 2.5-3.5 kg, were provided by Animal Experimental Center of Jiamusi University. The animal experiment had got confirmed consent from local ethic committee. Nano-HA was provided by Material Engineering College of Jiamusi University and dealt with routine hyperthermia/hypertension sterilization. In addition, hydroxyapatite was provided by Wuhan Industry University, and the diameter was 1.0-2.0 μm.METHODS: The experiment was carried out in the Experimental Animal Center of Jiamusi University from November 2001 to May 2006. All rabbits were randomly divided into experimental group and control group with 12 in each group. Bone defect in the diameter of 1.0 cm was produced on body of mandible. Nano-HA was used to repair the bone defect of rabbits in the experimental group, while hydroxyapatite was used to repair the bone defect of rabbits in the control group. At 1, 4, 8 and 12 weeks after operation, all rabbits were sacrificed. In addition, medical imaging analysis system was used to analyze generative quantity of tissue in the two groups; meanwhile, histological quality and quantity were also analyzed so as to observe histocompatibility and newborn osteogenesis. MAIN OUTCOME MEASURES: Histocompatibility and newborn osteogenesis.RESULTS: With the time passing by, the amount of repairing materials was decreased because of the combination with newborn tissue into bone in bone defect-repaired region in the experimental group. When it was closed to normal bone, the amount was stable. However, bony callus was not able to grow in materials in the control group. Results of correlation analysis demonstrated that materials were negatively straight-line correlation with newborn bone (r = -0.912 0, P < 0.01). During the repairing procedure of bone defect, newborn bone was closely correlative with Nano-HA; while, with the increase of newborn bone, the amount of repairing materials was decreased because of the combination with newborn tissue into bone.CONCLUSION: Nano-HA can combine with newborn bone tissue so as to rapidly generate bone, while it has an excellent biocompatibility.