胎儿牙齿硬组织发育的临床应用解剖

Clinical anatomy of tooth hard tissue development in fetus

目的:探讨国人胎儿牙齿硬组织发育状况.方法:对正常胎龄10～38周的胎儿上、下颌骨作连续切片,观察乳、恒牙胚及其相关结构发生规律.结果:牙体硬组织形成于14～20周,牙齿的增殖、钙化、萌出同时进行,牙釉质、牙本质厚度随胎龄增长而增加,各乳磨牙牙尖总是近颊尖最先发生,恒牙板总是位于乳牙胚舌侧.结论:国人牙体硬组织发育成熟较低,牙釉质、牙本质厚度与胎龄呈正相关.

Objective： To reveal the development of tooth hard tissue of fetus. Methods： Maxilla and mandible bone of normal fetus （gestational age from 10 to 38 weeks） were made into serial sections. The occurrence of tooth germ of deciduous and permanent teeth and dependency structure were observed. Results： Tooth hard tissue formed from 14 to 20 weeks; tooth proliferation, calcification and eruption occurred simultaneously; thickness of enamel and dentin ranged from 0. 14 to 0.89 mm, bucco-tip always occurred first in milk molars; dental lamina of permanent teeth always located at tongue side of milk tooth. Conclusion： Maturity of tooth hard tissue formation in Chinese is lower; thickness of enamel and dention have a positive correlation with gestational age.