新生大鼠成牙本质细胞及牙本质形成的光、电镜观察

目的:探讨成牙本质细胞的发育变化以及牙本质的结构发育特点.方法:取不同日龄新生大鼠的下颌切牙牙胚进行光、电镜观察.结果:成牙本质细胞由低柱状变为高柱状,并发生极化,细胞器渐增多,有分泌颗粒出现,细胞突起逐渐形成;形成的前期牙本质和牙本质在6～9 d达最厚,且胶原纤维较丰富而密集,牙本质小管多;成牙本质细胞突起贯穿前期牙本质和牙本质,并进入牙釉质中.结论:0～9 d日龄大鼠的下颌切牙牙胚正处于牙体组织的分泌形成期,是研究牙齿发育过程的很好的动物模型.

Observation of odontoblasts and dentin in neonatal mice with light and electronic microscopy

Objective: To explore the developing changes of structure in odontoblasts and dentin. Methods: Light and electronic microscopy were used. The lower incisor germs of mice were made into sections. Results: The shapes of odontoblasts of neonatal mice were different from short column to high column. Cell polarization was also found, and organellae increased. Thickest dentins were observed in mice of 6 to 9 days old. There was a lot of collagen and dentinal tubules in dentin. The processes of odontoblasts were from dentin to predentin, and then to enamel. Conclusion: The lower incisor germs of 0 to 9 days old mice were at secretory and formative period of tooth tissues, and this kind of mice were good animal models for study of tooth development.