自体骨髓基质干细胞-珊瑚羟基磷灰石修复下颌骨节段缺损的实验研究

目的应用骨髓基质干细胞（BMSCs）复合珊瑚羟基磷灰石（CHA）构建组织工程化骨，修复犬下颌骨节段性缺损。方法体外分离培养，成骨诱导扩增犬BMSCs，将第2代细胞复合CHA后修复5只犬自体下颌骨右侧3cm的节段缺损；6只犬植入单纯CHA作为对照，术后12、26、32周通过影像学、大体形态、组织学和生物力学的方法检测骨缺损的修复效果。结果BMSCs-CHA复合物生长良好。随时间延长，X线片和CT显示实验组连接处骨痂形成，实验对照组连接处始终愈合较差；32周大体观察实验组骨修复较好，组织学显示有板层骨形成，连接处骨性愈合，实验对照组有编织骨形成，连接处纤维愈合。实验组与正常对照组下颌骨力学强度差异无统计学意义。结论自体成骨诱导BMSCs复合CHA形成的组织工程化骨可修复犬下颌骨节段缺损。

Repair of canine segmental mandibular defects using autogenous bone marrow stromal cells and coralline hydroxyapatite

Objective To repair segmental mandibular defects with autogenous bone marrow stromal cells (BMSCs) and coralline hydroxyapatite. Methods Isolated BMSCs were in vitro expanded and osteogenically induced. In 11 canines, a 3 cm segmental mandibular defect in right mandible was created. Five canine's defects were repaired with cell-scaffold constructs made from induced BMSCs and coralline hydroxyapatite (CHA); Others were repaired with CHA as control. The engineered bone was evaluated by X-ray, CT, gross and histological examination,biomechanical test 12,26,32 weeks post-operation respectively. Results BMSCs grew well on the CHA. X-ray and CT images showed better callus formation at connection sites in experimental group over time while worse formation at connection sites eventually in control group. At 32 weeks post-operation in experimental group, the defects were well repaired grossly. Histologically, there were bony healing and lamellar bone formation,in experimental group fibrous healing and woven bone formation in control group. Biomechanical test revealed no significant difference between experimental group and normal control group. Conclusions Canine segmental mandibular defects can be ultimately repaired with the tissue-engineered bone generated by autogenous osteogenic BMSCs and CHA scaffold.