不同时期大鼠牙齿胚基各部分组织发育能力的研究

目的：比较不同发育时期牙胚各部分异位环境下的发育能力，为牙齿再生重组实验提供参考。方法：分离获取SD大鼠帽状期和钟状末期牙胚，分离成釉上皮与牙乳头间充质，分别将完整牙胚、牙间充质、成釉上皮剪碎后异位移植至同种异体大鼠肾被膜下。4周后取材，对移植物进行组织学观察。结果：帽状期牙胚碎组织块移植物中可见部分不规则的牙齿样结构形成。钟状末期牙问充质碎组织块移植组中既有牙本质牙髓复合体样结构形成，还能观察到大量骨样基质形成。而钟状末期成釉上皮碎组织块移植物生成的组织均为骨样的结构。结论：发育早期牙胚的碎组织较发育末期的牙胚碎组织具有更强的牙齿形成能力，所形成的牙齿结构完整包括釉质、牙本质以及牙髓且顺序正确，提示这个时期牙上皮和间充质之间信号网络所提供的微环境可以更加完善和充分地指导牙齿的发育。

Investigation of the development ability of tooth germ components from different stages

Objective： To investigate the potential of the differentiation and morphogenesis of tooth germs from separate development stage to provide an effective strategy for tooth regeneration research. Methods： Tooth germs of lower first molars from 14-day embryonic and one-day postnatal Sprague-Dawley rats were investigated the ectopic growth and development in renal capsules. Results： The HE results demonstrated that the tooth germ-related tissues at cap stage that could form regular tooth structures developed much better than those at late bell stage. Conclusion： In conclusion, dissociated tooth germs from early stage could recapitulate the embryonic tooth germ environment to favour normal tooth development, indicating that genetic signaling network from early development of tooth germ is necessary for odontogenesis. dental epithelial and mesenchymal tissues.