体外人牙髓细胞的矿化特性

为探讨体外人牙髓细胞的生物学特性，采用体外细胞连续培养、钙质染色、Ｘ射线能谱分析与透射电镜观察等方法，对体外人恒牙牙髓细胞的矿化特性进行了研究并与人牙龈成纤维细胞（ｈｕｍａｎｇｉｎｇｉｖａｆｉｂｒｏｂｌａｓｔｓ，ＨＧＦｓ）进行了比较。结果表明，人牙髓细胞在体外可以复层生长并形成细胞结节，ＨＧＦｓ则无此能力，牙髓细胞的碱性磷酸酶活性亦较ＨＧＦｓ者高；细胞结节钙质染色呈阳性，结节内钙磷含量明显增高；人牙髓细胞有许多与成牙本质细胞相似的超微结构特征，胞间基质中可见致密晶状小体。结果提示，体外连续培养的人牙髓细胞有向成牙本质细胞分化的可能，这可为研究人牙髓细胞的分化和矿化提供有价值的思路。

Mineralization of human dental pulp cells in continued culture

The purpose of this study was to understand the mineralization of human dental pulp cells in vitro. Pulp cells were isolated from human normal permanent teeth and cultured in normal tissue-culture medium. With continued culture, pulp cells formed cell nodules after 12-15 days, but no cell nodules were found from human gingiva fibroblasts. Pulp cells showed high alkaline phosphatase activity and the nodules were strongly stained by Von Kossa. Furthermore, the nodules showed high level of calcium and phosphorus by Energy-dispersive X-ray analysis and pulp cells had similar ultrastrusture with odontoblasts under TEM. The continued culture of pulp cells provides a useful system for studying differentiation and calcification of pulp tissue.