纳米羟基磷灰石/胶原/聚乳酸材料复合自体骨髓基质细胞修复犬下颌骨节段性缺损的实验研究

目的观察多孔块状纳米羟基磷灰石／胶原／聚乳酸材料（nHAC／PLA）作为支架与自体骨髓基质细胞（BMSCs）复合对大动物承力骨节段性缺损的修复能力，并探讨合适的术中固定方法，为临床应用提供实验依据。方法将多孔块状nHAC／PLA加工成3．0cm×2．0cm×1．0em的长方体状。体外培养犬髂骨来源的BMSCs，经过BrdU标记及成骨诱导后，与nHAC／PLA复合，并植人犬下颌骨3．Ocm长的节段性缺损处，经过6个月的饲养，通过影像学和组织形态学观察修复骨缺损的能力。并通过免疫组织化学的方法检测种子细胞的归宿。同时设自体髂骨移植组及单纯材料植入组作为对照。结果术后6个月，下颌骨缺损区被nHAC／PLA＋BMSCs复合形成的组织工程骨完全修复，形态恢复良好，大量成熟的骨组织充满缺损区的全层，材料大部分被吸收。从免疫组织化学染色结果看，组织工程骨细胞来源于种子细胞BMSCs。用钛重建板和微型钛板联合固定或单纯用钛重建板固定都可行。结论nHAC／PLA作为支架材料与自体BMSCs复合形成的组织工程骨可以修复大动物承力骨较大的节段性缺损，并可直接用钛重建板对其进行固定。

Repare of dog mandibular segmental defect with nano-hydroxyapatite/collagen/PLA material combined with autogenic bone marrow stromal cells

Objective To observe the reparing ability of tissue engineering bone compounded by nHAC/PLA with autogenic BMSCs on weight bearing bone＇s segmental defect of large animals. Methods nHAC/PLA in a shape of 3.0 cm × 2. 0 cm×1.0cm, after being compounded by BMSCs cultured in vitro,was implanted into dog mandibular segmental defect of 3.0cm. After 6 months, the state of bone formation in the repared area was observed by X-ray and histomorphology. The end-resuh of seed was examined by irnmunohistochemistry. Autogenous lilac bone translantation group and nHAC/PLA group served as control. Results Six months after operation, the mandibuler defect area was completely repaired by the tissue engineering bone compounded by nHAC/PLA and BMSCs. Tissue engineering bone cells came from seed cells. Both reconstruction plate combined with miniplate and pure reconstruction plate could fix the graft well. Conclusion The tissue engineering bone compounded by nHAC/PLA and autogenic BMSCs can repair weight bearing bone＇s segmental defect of large animals, and can be consolidated directly by titanium reconstruction plate.