3.5 POJA-L166
Title: Dentinogenesis in tooth development 1 (bell stage) Description: Electron microscopy, gerbil postnatal. At the bottom partly cross-sectioned odontoblasts with few organelles. 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. |
3.5 POJA-L167
Title: Dentinogenesis in tooth development 2 (bell stage) Description: Electron microscopy, gerbil postnatal. Higher magnification: At the bottom side of the predentin partly cross-sectioned odontoblasts with some organelles and many vesicular structures, the dark ones containing hydroxyapatite. Close to the odontoblasts a high concentration of secreted collagen fibers. Further away numerous matrix vesicles (filled with crystallites of hydroxyapatite) are localized associated with the collagen fibers. Note numerous light-stained odontoblastic branches are present. |
3.5 POJA-L153
Title: Ameloblasts and odontoblasts in tooth development (advanced bell stage) Description: Scheme electronmicroscopy, human embryo. From top to bottom: - Stellate reticulum consisting of a non- vascularized network of ectoderm- derived cells continuous with the cell layers of the stratum intermedium. - Columnar presecretory ameloblasts with their upper side (nuclear area) in close contact with the stratum intermedium, and at the distal side (secretion area) their basal lamina close to the predentin. - Epithelioid arranged odontoblasts with irregular extensions into the predentin (collagen fibers type I in extracellular matrix). - In close contact with the odontoblasts (basal nuclei) the network of fibroblast- like cells (so-called pulpal cells) producing collagen of the dental papilla (future pulp). 3.5 POJA-L82 Title: Odontoblast in tooth development Description: Scheme electron microscopy, human embryo. A columnar and irregular shaped cell (mesenchymal origin) with a taperwise odontoblastic process within the predentin. The bottom side is adjacent to the future pulp cells. The cell body contains many organelles and especially a well-developed Golgi area with prosecretoy granules. A cell web delimits the process from the supranuclear cytoplasm and laterally small junctional complexes (gap junctions) are localized. Keywords/Mesh: oral cavity, mouth, tooth, tooth development, odontoblast, predentin, matrix vesicle, ameloblast, histology, embryology, electron microscopy, POJA collection |