牙本质支架体外诱导兔骨髓干细胞分化

目的：探讨将人牙本质作为组织工程支架的可行性，采用不同的方式处理牙本质片，观察牙本质片处理后诱导兔骨髓基质干细胞贴壁附着生长的规律及成骨分化潜能。方法：将兔的骨髓基质干细胞分别接种于经机械去除前期牙本质加EDTA-柠檬酸脱矿处理（A组），标准根管预备-EDTA处理（B组）的牙本质片上，体外培养1周，扫描电镜观察细胞与牙本质片的附着情况，碱性磷酸酶、茜素红及Vonkossa染色观察兔骨髓基质干细胞成骨分化。结果：兔骨髓基质细胞附着在2种方式处理的牙本质片上生长良好，贴附紧密。B组牙本质片上细胞碱性磷酸酶表达阳性率高达80％，茜素红、Vonkossa染色观察到钙结节数量多于A组。结论：经标准根管预备一EDTA处理的人牙本质能有效促进骨髓基质干细胞增殖及成骨分化，可能成为一种理想的成骨生物支架，并为牙体牙髓疾病的治疗提供了新的思路。广西科学研究与技术开发计划项目（桂科攻1012400lA一42）

Effect of Dentin Matrix Scaffold on the Differentiation of Rabbit Bone Marrow Stem Cells In Vitro

Objective: To discuss the availability of human dentin as tissue engineering scaffolds.Using human dentin slices treated by different methods to observe the growth pattern and differentiation potential of rabbit bone marrow-derived mesenchymal stem cells(BMSCs).Mehtods: Rabbit BMSCs were seeded onto the healthy human dentin slice respectively treated by EDTA-citric acid(group A) or EDTA-root canal preparation(group B).Cell growth and proliferation on different dentin slices were determined with SEM after vitro culture for 1 week.Osteogenic differentiation of the rabbit BMSCs induced by different dentin slices was evaluated by alkaline phosphatase,alizarin red and Von Kossa staining after vitro culture for 9 days.Results: Rabbit BMSCs adhered and proliferated well on every disposed dentin slices.On dentin slices of group B,the positive rate of the cells expressed alkaline phosphatase were up to 80%,and at the same time,the number of calcium nodules was larger than group A by alizarin red,and Von kossa staining.Conclusion: Dentin slices treated by EDTA-root canal preparation method can effectively promote proliferation and osteogenic differentiation of BMSCs.As a result,it might be an ideal biological scaffold introducing bone regeneration.Further more,it provides new ideas for the treatment of dental pulp diseases.