Permanent teeth or adult teeth are the second set of
teeth
A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, ...
formed in
diphyodont mammals. In humans and old world simians, there are thirty-two permanent teeth, consisting of six
maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...
ry and six
mandibular molars, four maxillary and four mandibular
premolars, two maxillary and two mandibular
canine
Canine may refer to:
Zoology and anatomy
* a dog-like Canid animal in the subfamily Caninae
** ''Canis'', a genus including dogs, wolves, coyotes, and jackals
** Dog, the domestic dog
* Canine tooth, in mammalian oral anatomy
People with the surn ...
s, four maxillary and four mandibular
incisors.
Timeline
The first permanent tooth usually appears in the
mouth at around six years of age, and the mouth will then be in a transition time with both primary (or
deciduous dentition) teeth and permanent teeth during the mixed dentition period until the last primary tooth is lost or shed.
The first of the permanent teeth to erupt are the permanent first molars, right behind the last 'milk' molars of the primary dentition. These first permanent molars are important for the correct development of a permanent dentition. Up to thirteen years of age, 28 of the 32 permanent teeth will appear.
The full permanent dentition is completed much later during the permanent dentition period. The four last permanent teeth, the third molars, usually appear between the ages of 17 and 38 years; they are considered
wisdom teeth.
Pathology
It is possible to have extra, or "supernumerary," teeth. This phenomenon is called
hyperdontia
Hyperdontia is the condition of having supernumerary teeth, or teeth that appear in addition to the regular number of teeth (32 in the average adult). They can appear in any area of the dental arch and can affect any dental organ. The opposite ...
and is often erroneously referred to as "a third set of teeth." These teeth may erupt into the mouth or remain impacted in the bone. Hyperdontia is often associated with syndromes such as
cleft lip and cleft palate
A cleft lip contains an opening in the upper lip that may extend into the nose. The opening may be on one side, both sides, or in the middle. A cleft palate occurs when the palate (the roof of the mouth) contains an opening into the nose. The te ...
,
tricho-rhino-phalangeal syndrome,
cleidocranial dysplasia, and
Gardner's syndrome
Gardner's syndrome (also known as Gardner syndrome, familial polyposis of the colon, or familial colorectal polyposis) is a subtype of familial adenomatous polyposis (FAP). Gardner syndrome is an autosomal dominant form of polyposis characteriz ...
.
See also
*
Deciduous dentition
*
Tooth development
Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. For human teeth to have a healthy oral environment, all parts of the tooth must develop during appropriate st ...
*
Tooth eruption
*
Teething
*
Dentition
References
* Ash, Major M. and Stanley J. Nelson, 2003. ''Wheeler’s Dental Anatomy, Physiology, and Occlusion.'' 8th edition.
External links
{{Authority control
Types of teeth