Early Tooth Development Flashcards
What are the names of the tooth development stages?
What 2 types of cells are present here?
Dental lamina, initiation, bud stage, cap stage, bell stage, eruption.
Mesenchymal and epithelial cells.
What is morphogenesis?
When the shape of a cell/tooth changes.
Determination of tooth crown shape by epithelial folding due to a combination of cell proliferation and cell movement.
What are the 3 main swellings which are where the dental tissues originate from?
Frontonasal process (gives rise to the nose and forehead), 1st brachial arch (maxillary process, mandibular arch), 2nd brachial arch.
Where do dental tissues originate from?
Epithelium (oral epithelium and ectoderm).
Mesenchyme (derived from neural crest cells).
What does epithelium and mesenchyme form?
Epithelium = enamel Mesenchyme = dentin, dental pulp, cementum, peridontal ligament, alveolar bone socket
What tissue forms the brain in later development?
Neural ectoderm.
Where do cranial neural crest cells delaminate?
At the border of the neural and non-neural ectoderm.
Where do cranial neural crest cells migrate into?
Into the branchial arches. R1, R2 and midbrain form from the maxillary and the mandible.
What transition must neural crest cells undergo?
What cells can these then differentiate to?
Epithelial to mesenchymal transition. The epithelium of the ectoderm folds and this is where the transition occurs.
Ectomesenchyme can then differentiate to chondroblasts, osteoblasts, fibroblasts, odontoblasts and cementoblasts.
Where do incisors develop from?
Where do teeth further back develop from?
Upper nasal process.
The mandible and maxilla.
What are the two tissues on the oral side of the 1st branchial arch and the frontal nasal process which form the entire tooth?
Oral ectoderm and ectomesenchyme.
What happens in week 6 of initiation to the mouth?
Formation of the primary epithelial band. This develops along the oral side of the maxilla and mandible. It is a continuous band of thickened epithelium.
What does the primary epithelial band correspond to?
The thickening of the oral epithelium.
Cells within the oral epithelium change their plane of division. They divide perpendicular to the plane of the division.
What are the two subdivisions that the primary epithelial band gives rise to?
Lingually = dental lamina (gives rise to the teeth) Buccal = vestibular lamina (cells die and form the space between the teeth)
What week is there initiation of tooth formation at the dental lamina?
How can this be seen?
8th week
Series of swellings develop on the deep surface of the dental lamina. 20 swellings will form in the mouth to form each tooth.
