Adult and "Baby" teeth diagram.
Dental anatomy or anatomy of teeth is a field of ana-
tomy dedicated to the study of human tooth structures.
The development, appearance, and classification of
teeth fall within its purvue. (The function of teeth as
they contact one another falls elsewhere, under dental
occlusion.) Tooth formation begins before birth, and
teeth’s eventual morphology is dictated during this
time. Dental anatomy is also a taxonomical science: it is
concerned with the naming of teeth and the structures
of which they are made, this information serving a prac-
tical purpose in dental treatment.
Usually, there are 20 primary ("baby") teeth and 28
to 32 permanent teeth, the last four being third molars
or "wisdom teeth", each of which may or may not grow
in. Among primary teeth, 10 usually are found in the
maxilla (upper jaw) and the other 10 in the mandible
(lower jaw). Among permanent teeth, 16 are found in
the maxilla and the other 16 in the mandible. Most of
the teeth have distinguishing features.
Tooth development 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
Radiograph of lower right (from left to right) third, second, and
first molars in different stages of development.
humans. For human teeth to have a healthy oral envir-
onment, enamel, dentin, cementum, and the periodonti-
um must all develop during appropriate stages of fetal
development. Primary (baby) teeth start to form
between the sixth and eighth weeks in utero, and per-
manent teeth begin to form in the twentieth week in
utero. 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 de-
termining the processes that initiate tooth development.
It is widely accepted that there is a factor within the tis-
sues of the first branchial arch that is necessary for the
development of teeth.