骨复合材料结合生物膜即刻修复免下颌骨缺损

背景:近年来虽然有用不同方法处理过的异体骨、异种骨及各种组织工程材料骨问世,但临床上对颌骨缺损后骨量不足的治疗仍然没有较理想的解决方法.目的:通过动物实验观察较大下颌骨缺损及伴牙脱位的下颌骨缺损后骨复合材料结合生物膜即刻修复的效果.设计、时间及地点:对比观察动物实验,于2006-03/07在浙江大学动物实验室完成.材料:Bio-oss骨代卡于料与自体骨骨粉混合的比例为1:1,重组入骨形成蛋白2冻干粉溶于自体新鲜血液的比例为0.25 mg:1 mL.将骨粉混合物用含人骨形成蛋白的血液湿润,以容易粘到药匙上方便塑形为度.方法:取10只新西兰大白兔,在双侧下颌骨体部下缘各造成15 mm×6 mm×5 mm连续性骨缺损,随机选取一侧植入骨复合材料加Bio-gide膜,该侧作为骨复合材料加Bio-gide膜组.另一侧缺损直接拉拢缝合作为空白对照组.其余30只新西兰大白兔为骨复合材料加Bio-gide膜及再植牙组,在一侧下颌骨下缘上方造成15 mm×6 mm×8 mm的骨缺损伴牙脱位,植入骨复合材料加Bio-gide膜,并将脱位牙齿再植于原处.主要观察指标:大体观察植入材料部位和材料结合情况及有无成骨、再植牙松动等.×射线摄片和组织学观察骨缺损处新骨形成情况.结果:术后12周空白对照组下颌骨缺损处形成一较原截骨范围略小的骨缺损,骨复合材料加Bio-gide膜组下颌骨缺损区基本由新生骨组成,X射线观察骨缺损区密度接近正常骨组织,组织学观察骨植入物基本形成板状骨,骨复合材料加Bio-gide膜及再植牙组动物自体再植牙有17只无明显松动,X射线观察有13只根尖无透射区,组织学观察有13只出现替代性吸收.结论:该种骨复合材料结合牛物膜即刻修复较大下颌骨缺损效果良好,在其上自体牙再植近期效果尚可.

Bone composite and biomembrane in repairing rabbit mandibular defect

BACKGROUND: There are various methods for management of allogeneic bone, xenogeneic bone and various tissue engineered materials, but there is no ideal method for treatment of insufficient bone mass following jaw defects. OBJECTIVE: To observe the repair efficiency of bone composite and biomembrane following large mandibular defect and mandibular defect combined with tooth luxation in animal studies. DESIGN, TIME AND SETTING: The controlled observational animal study was performed at the Animal Laboratory of Zhejiang University from March to July 2006. MATERIALS: The mixed proportion of Bio-oss material and autologous bone powder was 1:1. The proportion of recombinant human bone morphogenetic protein-2 freeze-dry powder dissolved in autologous fresh blood was 0.25 mg:1 mL. Bone powder mixture was moistened by blood containing human bone morphogenetic protein to stick on the medicine spoon for moulding easily. METHODS: Ten New Zealand rabbits were selected. Consecutive bone defects (15 mm×6 mm×5 mm) were made in the inferior border of bilateral mandible body. Bone composite and Bio-gide membrane were randomly implanted into one side (bone composite + Bio-gide membrane group). Another side was directly sutured as blank control group. The remaining 30 rabbits were considered bone composite + Bio-gide membrane + implantation tooth group. A bone defect (15 mm×6 mm×8 mm) was made at the upper site of inferior border of mandible, with the combination of tooth luxation. Bone composite and Bio-gide membrane were implanted, and the luxation teeth were implanted into the original site. MAIN OUTCOME MEASURES: Implantation site, composite conjugation, loose of bone formation and implanted teeth were generally observed. New bone formation at the bone defect site was observed using radiograph and histological method. RESULTS: At 12 weeks following surgery, a bone defect, which was smaller than the original bone, was found at the mandibular defect site in the blank control group. New bones were visible in the mandibular defect site in the bone composite + Bio-gide membrane group. Radiograph demonstrated that the density of defect bone site was similar to normal bone tissue. Histological method revealed that bone implant formed board-shaped bone. No significant loose was detected in implanted teeth of 17 rabbits in the bone composite + Bio-gide membrane + implantation tooth group. Radiograph demonstrated that no transparent area was found in the root tip of 13 rabbits. Histological method showed replacement resorption in 13 rabbits. CONCLUSION: Bone composite combined with Bio-gide membrane for repairing large mandibular defect obtained good efficiency. The outcome of autologous tooth implantation is acceptable in the near future.