Cap stage of tooth development (early)

The dental lamina connects the developing tooth germ with the oral ectoderm.

The tooth germ, first identifiable at the cap stage, is the collection of cells that develop into the tooth. The tooth germ consists of all identifiable ectoderm and ectomesenchyme tissue, including the inner enamel epithelium and outer enamel epithelium (ectoderm) as well as the dental papillae and the dental follicle (ectomesenchyme).

The enamel organ develops from the dental lamina during the cap stage of tooth development. It consists of an inner enamel epithelium, an outer enamel epithelium and a central region containing a stellate reticulum.

The inner enamel epithelium forms the concave portion of the enamel organ. It consist of columnar cells that differentiate into enamel-forming ameloblasts.

The outer enamel epithelium serves protective and supportive roles for the tooth germ.

The cervical loop is the site where the inner and outer enamel epithelia meet. It will elongate during tooth development to form Hertwig’s epithelial root sheath.

The stellate network supports the inner enamel epithelium and consists of star-shaped cells derived from the epithelium. Their morphology results from secretion of glycosaminoglycans and the resultant attraction of the water into the enamel organ.

The dental papilla is formed of ectomesenchymal cells beneath the enamel organ and will form the majority of the dental pulp.

The dental follicle, also called the dental sac, surrounds the enamel organ and dental papilla in the apical regions of the tooth germ. The follicle differentiates into cementoblasts that deposit cementum, fibroblasts that deposit collagen fibers as part of the periodontal ligament, and osteoblasts that deposit alveolar bone.

Successional lamina develop as an outgrowth from the original dental lamina and form the permanent teeth.