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 in 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 presecretory granules. A cell web delimits the process from the supranuclear cytoplasm and laterally small junctional complexes (gap junctions) are localized. |
3.5 POJA-L83 Title: Presecretory ameloblast in tooth development Description: Scheme electronmicroscopy, human embryo. The ectodermal-derived cell appears as tall columnar with fingerlike extensions (dependent on the development stages) at their distal side (secreting area=’functional base’). These extensions are formed as the cell withdraws during the production of initial enamel. The supranuclear area is well developed with a large Golgi area and secretion granules. |
3.5 POJA-L153
Title: Ameloblasts and odontoblasts in tooth development (advanced bell stage) Description: Scheme electronmicroscopy, human embryo. Description: 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-L154 Title: Advanced bell stage with ameloblasts and odontoblasts in tooth development Description: Stain Azan, human embryo. From top to bottom: - Stellate reticulum consisting of a non- vascularized network of ectoderm- derived cells. - 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) oriented towards predentin (blue). - Predentin with Korff’s fibers. - Tall columnar odontoblasts in a epithelioid arrangement with their secretion area close to the predentin (blue). - Network of mesenchymal derived fibroblast-like cells (so-called pulpal cells) in the dental papilla (future pulp); note blood vessels. Keywords/Mesh: oral cavity, mouth, tooth development, ameloblast, enamel, odontoblast, predentin, histology, embryology, electron microscopy, POJA collection |