Dentinogenesis in tooth development - bell stage, gerbil, postnatal

Electronmicroscopy. At the top right corner side the distal cytoplasmic parts of presecretory ameloblasts resting on a thin grey basal lamina. In the central area predentin with collagen fibers (grey patches) and cross-sectioned small odontoblastic branches. In between them dispersed numerous dark-stained calcified matrix vesicles (free vesicles with crystallites of hydroxyapatite). The amount of matrix vesicles as well as the lightly stained odontoblastic extensions tend to increase close to the basal lamina. This indicates localization of future dentin.