Bell stage of the tooth development - human, embryo; low magnification

Stain: Azan. From top to bottom: Stratified ectoderm with a distinct basal layer (red line) of cuboid cells; Dental lamina giving rise to the bell stage (left) and to the primordium of permanent tooth (right); Odontogenic organ (future deciduous tooth) surrounded by fibrous tooth follicle; Outer dental epithelium encloses the stellate reticulum consisting of a network of ectoderm-derived cells; In the cuspal tip inner dental epithelium is seen as a dark red zone of future ameloblasts; predentin is deposited as a blue rim apposed to the odontoblastic cells; Compact network of fibroblast-like cells (so-called pulpal cells) of the dental papilla (future pulp) which extends outside the cervical loop; Blood vessels of the papilla and tooth follicle are shown; At the bottom alveolar bone formation (dark blue).