Electron microscopy of the differentiating rat incisor ameloblast

摘要: Incisors of adult rats were fixed with a glutaraldehyde—OsO4 sequence. The enamel organs embedded in Araldite without decalcification. Two phases differentiation preameloblasts could be defined. In the early phase, have many free ribosomes and microtubules. cells elongate, Golgi vesicles move into apex (toward predentin), dense material coarse granular texture appears between within predentin. late phase differentiation, there is increasing evidence synthetic activity lysosome formation. Preameloblast processes push through basal lamina invade Odontoblast come contact apical border preameloblasts. Electron which may an precursor extracellular space preameloblast bases. After has completely disappeared, predentin starts to mineralized. Enamel deposition begins when complete layer calcified dentin present. Origin nature very first matrix not clear. thin been deposited, large droplets appear at ameloblasts preparation for formation Tomes' processes.