Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. Although many diverse species have teeth, non-human tooth development is largely the same as in humans. For human teeth to have a healthy oral environment, enamel, dentin, cementum, and the periodontium must all develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth weeks, and permanent teeth begin to form in the twentieth week. If teeth do not start to develop at or near these times, they will not develop at all.
A significant amount of research has focused on determining the processes that initiate tooth development. It is widely accepted that there is a factor within the tissues of the first branchial arch that is necessary for the development of teeth.
In vertebrates, several specializations of epithelial tissue ('phanères') generate after thickening specific structures: keratinized structure (hair, nails) or exoskeletons structure (scales, teeth). Placoids scales and teeth of sharks are considered homologous organs.
Read more about Tooth Development: Overview, The Developing Tooth Bud, Formation of The Periodontium, Nerve and Vascular Formation, Tooth Eruption, Nutrition and Tooth Development, Abnormalities, Molecular Biology
Famous quotes containing the words tooth and/or development:
“How sharper than a serpent’s tooth it is
To have a thankless child.”
—William Shakespeare (1564–1616)
“Somehow we have been taught to believe that the experiences of girls and women are not important in the study and understanding of human behavior. If we know men, then we know all of humankind. These prevalent cultural attitudes totally deny the uniqueness of the female experience, limiting the development of girls and women and depriving a needy world of the gifts, talents, and resources our daughters have to offer.”
—Jeanne Elium (20th century)