作者以前的研究已表明:大白鼠切牙和磨牙牙髓,对实验性穿髓引起的外源性刺激反应不同。在牙髓暴露后切牙牙髓没有显著变化,而磨牙牙髓中有硬组织形成。在本研究中,对磨牙牙髓产生的硬组织进行了超微结构观察。本实验中形成的硬组织有两层不同结构,即骨样牙本质和正牙本质样结构。骨样牙本质结构见于靠近暴露面的牙髓,与这种新形成硬组织有关的细胞类似成骨细胞或造牙本质细胞。这些细胞含有发育很好的粗面内质网和高尔基氏器,并有活跃的蛋白质形 Previous studies by the authors have shown that the alveolar response to the experimental perforin is different in the incisor and molar dental pulp of rats. There was no significant change in dental pulp after dental pulp exposure, while there was hard tissue formation in the molar. In this study, the ultrastructure of hard tissue produced by tooth pulp was observed. The hard tissue formed in this experiment has two layers of different structures, namely the bone-like dentin and the orthodontic-like structure. Bone-like dentin structure is found near the exposed surface of the pulp, with this new hard tissue-forming cells similar to osteoblasts or dentin cells. These cells contain well-developed rough endoplasmic reticulum and Golgi and have an active protein-like