- tooth (t
th)
[ L. dens; Gr. odous ]
- 1. any of the hard calcified
structures set in the alveolar
processes of the mandible and
maxilla for mastication of food.
In humans, there are two sets of
teeth (dentes[TA]),
deciduous and
permanent. Each tooth
consists of three parts: the
crown (see
corona dentis), the
neck (see
cervix dentis), and the
root (see
radix dentis). The solid
part includes
dentin, forming most of the
tooth and resembling true bone;
enamel, a very hard
inorganic substance, covering
the crown; and
cementum, covering the root.
In the center is the soft pulp
(see
pulpa dentis). See also
dentition. 2. a structure
resembling the tooth of an
animal.
-

- Schematic cross
section of an anterior (left)
and a posterior (right) tooth in
the maxilla.
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Tooth
abutment
tooth, one selected to
support a bridge on the basis of
the total surface area of a
healthy attachment apparatus.
See also
abutment (def. 2).
accessional teeth, the
molar teeth of the permanent
dentition, so called because
they do not supplant any
deciduous predecessors in the
dental arch. Cf.
succedaneous teeth.
anatomic teeth,
artificial teeth that duplicate
the anatomic forms of natural
teeth.teeth that have prominent
pointed or rounded cusps on the
masticating surfaces and are
designed to occlude with the
teeth of the opposing denture or
natural dentition.
ankylosed tooth,
submerged t.
anterior teeth, the
incisor and
canine teeth, which are in
the anterior parts of the dental
arches. Called also
labial or
morsal teeth.
artificial tooth, one
fabricated for use as a
substitute for a natural tooth
in a prosthesis, usually made of
porcelain or resin. See also
denture.
auditory teeth, auditory
teeth of Huschke,
dentes acustici.
tooth of axis,
dens axis.
baby teeth,
deciduous teeth.
bicuspid teeth,
premolar teeth.
buccal teeth,
posterior teeth.
canine tooth, the tooth
immediately lateral to the
lateral, or second, incisor; it
has a long conical crown and the
longest, most powerful root of
all the teeth. Called also
canine,
cuspid,
cuspid t., and
dens caninus[TA].
carnassial tooth, a large
molar or premolar of a
carnivore, specialized for
shearing and tearing.
cheek teeth,
posterior teeth.
cog tooth of malleus,
spur of malleus.
conical tooth,
peg t.
connate tooth,
geminate t.
corner tooth, the third
incisor on either side of each
jaw in the horse. Called also
corner.
cross-bite teeth,
artificial posterior teeth
designed to permit positioning
of the modified buccal cusps of
the upper teeth in the fossae of
the lower teeth.
cross-pin teeth,
artificial teeth in which the
pins are inserted horizontally.
cuspid tooth,
canine t.
cuspless tooth, any tooth
deprived of a cusp; particularly
an artificial tooth designed
without cuspal prominences on
the occlusal surface.
deciduous teeth, the 20
teeth of the first dentition,
which are shed and replaced by
the permanent teeth. They begin
to calcify at about the fourth
month of fetal life, and near
the end of the sixth month they
all have begun to develop. The
first incisors appear at about
the age of 6 1/2 months; they
are followed by the second
incisors 1/2 month later; and,
within 1 1/2 months, by the
maxillary incisors. The
deciduous molars begin eruption
a 1 year, and the deciduous
canines approximately 4 months
later. All the deciduous teeth
are expected to erupt by the
time the child is 2 1/2 years of
age. The deciduous dentition
formula (one side) is as
follows:

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- diatoric teeth,
artificial teeth with holes in
their bases into which the
denture base material flows and,
when processed, attaches the
teeth to the base. Called also
pinless teeth.
drifting tooth,
wandering t.
embedded tooth, one that
is unerupted because of lack of
eruptive force.
tooth of epistropheus,
dens axis.
eye tooth, colloquial
term for a
canine tooth of the upper
jaw.
Fournier teeth,
Moon teeth.
fused teeth, partial or
complete fusion of two or more
individual teeth.
geminate tooth, a tooth
with a single root and root
canal, but with two completely
or incompletely separated
crowns, resulting from
invagination of a single tooth
germ, causing incomplete
formation of two teeth. Called
also
connate t.
Goslee tooth, an
interchangeable artificial tooth
attached to a metal base.
hag teeth, upper medial
incisors that are widely
separated.
Horner teeth, incisor
teeth that are horizontally
grooved owing to a deficiency of
enamel.
Hutchinson teeth, a tooth
abnormality seen in congenital
syphilis, in which the
permanent incisors have a
screwdriverlike shape, sometimes
with notching of the incisal
edges or depressions in the
labial surfaces above the
cutting edge. Called also
Hutchinson incisors and
screwdriver teeth.
impacted tooth, one
prevented from erupting by a
physical barrier. See also
unerupted t.
incisor tooth, either of
the two most frontal teeth in
each jaw, one on either side of
the midline; it has a long root
and is adapted for cutting.
Symbol I. Called also
incisor and
dens incisivus[TA].
labial teeth,
anterior teeth.
malacotic teeth, teeth
that are soft in structure and
are abnormally susceptible to
caries.
malposed tooth, a tooth
out of its normal position.
mandibular teeth, the
teeth of the mandible, or lower
jaw.
maxillary teeth, the
teeth of the maxilla, or upper
jaw.
metal insert tooth, an
artificial tooth, usually of
acrylic resin, containing an
inserted ribbon of metal or a
cutting blade in the occlusal
surface, with one edge exposed;
sometimes used in removable
dentures.
milk tooth,
predeciduous t.neonatal
t.deciduous
t.
molar teeth, the most
posterior teeth on either side
in each jaw, totaling 8 in the
deciduous dentition (2 on each
side, upper and lower), and
usually 12 in the permanent
dentition (3 on each side, upper
and lower). They are the
grinding teeth, having large
crowns with broad chewing
surfaces. The upper molars
characteristically have 4 major
cusps and three roots. The lower
first molars characteristically
have 5 cusps, and the remaining
lower molars 4 cusps. Normally
all lower molars have two roots.
The third molars (“wisdom
teeth”) are often malformed, but
when developed normally their
crown and root form corresponds
in general with neighboring
molars in the same jaw. Symbol
M. Called also
molars and
dentes molares[TA].
molar tooth, third, the
tooth most distal to the medial
line on either side in each jaw,
so called because it is the last
of the permanent dentition to
erupt, usually at the age of 17
to 21 years. Called also
wisdom t.,
third molar,
dens molaris tertius[TA],
and
dens serotinus[TA
alternative].
Moon teeth, small, domed
first molars observed in
patients with congenital
syphilis.
morsal teeth,
anterior teeth.
mottled teeth, see under
enamel.
mulberry tooth,
mulberry molar.
natal tooth,
predeciduous t.
neonatal tooth, one that
erupts within the first month of
life. Called also
milk t.
nonanatomic teeth, a term
applied to artificial teeth the
occlusal surfaces of which are
especially designed on the basis
of engineering concepts, without
regard to the features of
natural teeth.
peg tooth, peg-shaped tooth,
one having a conical form,
whose sides converge or taper
together incisally, instead of
being parallel or diverging
mesially and distally; a
condition frequently observed in
the maxillary lateral incisor.
Called also
conical t.
permanent teeth, the 32
teeth of the second dentition,
which begin to appear in humans
at about 6 years of age. The
first molars appear first,
followed by the mandibular
central and lateral incisors,
maxillary central incisors,
maxillary lateral incisors,
mandibular canines, first
premolars, second premolars,
maxillary canines, second
molars, and third molars. They
take their position posterior to
the deciduous teeth and erupt in
succession, whenever the jaws
grow sufficiently to accommodate
them. Exfoliation of the
deciduous teeth is brought about
by resorption of their roots,
and the succedaneous permanent
teeth take their place. The
permanent dentition formula (one
side) is as follows:

where I =incisor;
C =canine;
P =premolar;
M =molar.
Called also
dentes permanentes[TA]
and
permanent or
secondary dentition.
.jpg)
Models of permanent
teeth (A); permanent canine (B);
and permanent first molar (C).
pink tooth of Mummery,
internal tooth resorption
(def. 1).
pinless teeth,
diatoric teeth.
posterior teeth, the
premolar and
molar teeth, which are in
the posterior parts of the
dental arches. Called also
buccal or
cheek teeth.
predeciduous tooth, any
tooth present at birth, which
may be normal in all respects or
may represent a hornified
epithelial rootless structure,
found on the gingivae over the
crest of the ridge before
eruption of the deciduous teeth.
Called also
dentia praecox,
milk or
natal t., and
predeciduous dentition.
premature teeth,
deciduous teeth that erupt prior
to the end of the third month of
life, or permanent teeth that
erupt prior to the end of the
fourth year of life. Called also
dentia praecox and
precocious or
premature dentition. See
also
predeciduous teeth.
premolar teeth, the
permanent teeth between the
canines and the molars; there
are two on either side in each
jaw. The upper premolars are
bicuspid and the lower have from
one to three cusps. Premolars
are succedaneous to the
deciduous molar teeth. Symbol P.
Called also
dentes premolares[TA],
premolars,
bicuspids, and
bicuspid teeth.in animals
other than humans, the teeth
that succeed the deciduous
molars regardless of the number
to be succeeded.
primary teeth,
deciduous teeth.
pulpless tooth, a tooth
from which the pulp has been
extirpated.
rake teeth, teeth that
are widely separated.
rootless teeth,
dentinal dysplasia.
sclerotic teeth, teeth
that are hard in structure and
resistant to caries.
screwdriver teeth,
Hutchinson teeth.
shell tooth, a condition
characterized by dysplasia of
the dentin, associated with
essentially normal enamel, thus
resulting in an extremely large
pulp chamber and root canal that
give the affected tooth the
appearance of a shell.
snaggle tooth, a tooth
out of proper line with the
others.
stomach tooth, a
canine tooth of the
mandible.
straight-pin teeth,
artificial teeth in which the
pins are inserted vertically.
submerged tooth, a
deciduous tooth, usually a
second mandibular molar, that
has undergone resorption and has
become ankylosed to the bone,
thus preventing its exfoliation
and subsequent replacement by a
permanent tooth; it appears to
be submerged below the level of
occlusion in relation to the
adjacent permanent teeth. Called
also
ankylosed t.
succedaneous teeth,
successional teeth, the
permanent teeth that have
deciduous predecessors in the
dental arch. Cf.
accessional teeth.
superior teeth, the teeth
of the upper jaw, or maxilla.
supernumerary teeth,
supplemental teeth, natural
teeth in excess of the number
normally present in the jaw.
.jpg)
Supernumerary teeth in
cleidocranial dysplasia.
temporary teeth,
deciduous teeth.
tube teeth, artificial
teeth having a vertical,
cylindrical aperture from the
center of the base up into the
body of the tooth, into which a
pin may be placed or cast for
attachment of the tooth to the
denture base.
Turner tooth, enamel
hypoplasia of a single tooth,
most commonly one of the
permanent maxillary incisors or
a maxillary or mandibular
premolar, resulting from local
infection or trauma. Called also
Turner hypoplasia.
unerupted tooth, one that
failed to erupt; the presence of
multiple unerupted permanent
teeth is sometimes referred to
as
pseudoanodontia. See also
embedded t. and
impacted t.
vital teeth, teeth to
which the nerve and vascular
supply is intact.
wandering tooth, a tooth
that drifts from its normal
position in the dental arch.
Called also
drifting t.
wisdom tooth,
third molar t.
wolf tooth, a vestigial
first premolar tooth sometimes
present in the jaw of a horse.
zero degree teeth,
artificial teeth which have no
cusp angles in relation to the
horizontal on their occlusal
surfaces.
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