人牙胚体外16d培养模型的建立

Establishment of human tooth germ culture model for longer term(16 days) in vitro

目的建立人牙胚体外较长时间(16 d)的培养模型。方法将处于分泌前期人牙胚采用Trowell型支架培养法,应用BGJb培养基(含L-抗坏血酸200 mg/L,维甲酸1×10-7mol/L),37℃,5%CO2+95%空气条件下进行培养。体外培养4、8、12、16 d后随机抽取牙胚进行常规包埋、切片染色,组织学观察。结果在培养过程中牙胚发育良好,形成明显的牙尖形态,造釉器分化为4层,在培养第16天牙尖部内釉上皮细胞出现核碎裂,牙乳头细胞之间出现裂隙。结论应用此方法能够将处于分泌前期的人牙胚在体外培养16 d。

Objective To establish a longer term（ 16 days） culture model of human tooth germ in vitro. Methods We cultured the human tooth germ during presecretory stage in BGJb medium（contained 200 mg/L L-ascorbic acid and 1 ×10^-7mol/L retinoic acid） in a Trowell type culture system in 37 ℃ and 5 % CO2 gas condition. After 4,8,12,16 days＇ culture, we took out some tooth germs randomly, and then fixed and parafifin-embedded by standard procedures. The tissue blocks were serially sectioned and stained with hematoxylin-eosin（H＆E） and observed under light microscope.Results The tooth germs developed well and shaped obvious dental cusp,and the enamel organ formed four stratums. After 16 days＇ culture, the inner enamel epithelium cells of the cusp showed cytonecrosis and karyon disintegration. Fissura emerged between the dental papilla cells. Conclusion We cultured the human tooth germ for 16 days by the method in vitro and established the longer-term culture model of human tooth germ.