The Permanent Canines, Maxillary and Mandibular Permanent... · Maxillary canine The labial and lingual outline is a series of curves except for the angle made by the tip of cusp.

The Permanent Canines,

Maxillary and Mandibular

Dr Preeti Sharma

Reader

Oral & Maxillofacial Pathology

Dr. Preeti Sharma, Subharti Dental College, SVSU

The four canines are placed at the four

corners of the mouth.

They are the longest teeth in the mouth.

The middle labial lobes are developed

incisally into strong well-formed cusps.

Because of labiolingual thickness of crown

and root and anchorage in alveolar process of

jaws, these are most stable in the mouth.

Crown shape promotes cleanliness.


The position and form of teeth and bony

portion on the labial surface of teeth called

canine eminence has a cosmetic value.

Ensures normal facial expressions at corners

of mouth.

They support laterals and premolars in

function.


Maxillary canine

The labial and lingual outline is a series of curves

except for the angle made by the tip of cusp. The cusp

has a mesioincisal and distoincisal ridge.

From labial view, the mesial half of the crown

resembles incisor and distal half premolar.

The tooth is wider labiolingually to offset the

directional lines of forces.

Labiolingually 1mm wider than central incisor and

mesiodistally 1mm narrower.


Cingulum shows greater development than

that of central incisor.

The root is thick labiolingually, with

developmental depressions mesially and

distally for better anchorage.


Labial Aspect

The crown is narrower than central incisor.

The cervical line is convex labially, with convexity

towards root portion.

Mesially, crown is convex from cervix to center of

mesial contact area with slight concavity above the

contact area. Contact area is at junction of incisal and

middle thirds.

Distally, the outline is concave between cervical line

and distal contact area (center of middle third of

crown).


The cusp tip is on line with the center of root.

The cusp has mesial (shorter) and distal

slopes.

On labial surface shallow depressions are

found that forms three labial lobes.

The middle lobe shows greater development

which produces a ridge on the labial surface of

crown. All areas mesial to this ridge exhibit

convexity except for some insignificant

development lines in enamel.


The root looks conical in form with a bluntly

pointed apex.

A sharp curve may be seen in the apical third,

mostly distally.

The surface of root is smooth and convex at

all points.


Lingual Aspect

The crown and root are narrower lingually than

labially.

The cervical line shows a more even curvature.

The cingulum is large and may be pointed like small

cusp.

Definite ridges may be found cervical to cingulum.

Well developed ridge may be seen which is

confluent with the cusp tip.


Mesial and distal lingual fossae may also be

seen.

Lingual portion of root is also narrower than

labial.

Lingual ridge of root is narrow but smooth and

convex.


Mesial Aspect

The outline is wedge shaped, greatest

measurement at the cervical third.

Crest of curvature is found at a level more

incisal.

Labial outline exhibits more convexity from

cervical line to the cusp tip than maxillary

central incisor.


Lingual outline is a convex line describing the

cingulum which straightens out as thye middle third

is reached and becomes convex again at the incisal

third.

Flattened area labially at cervical third of crown.

The cervical line curves towards the cusp, an

average 2.5mm.

The mesial surface of root appears broad, with a

shallow developmental depression for part of the

root length.


Distal Aspect

Is somewhat the same except that:

i. Cervical line exhibits less curvature towards cusp

ridge.

ii. DMR is heavier and more irregular in outline.

iii. Surface more concave usually above the contact

area.

iv. Developmental depression is more pronounced.


Incisal Aspect

Labiolingual dimension is greater than the

mesiodistal.

Tip of cusp is just labial to center of the

crown labiolingually and mesial to the center

mesiodistally.

Crown gives the impression of having all of

distal portion stretched to make contact with

first premolar.


A line bisecting the cusp and cusp ridges

drawn in the mesiodistal direction is almost

always straight and bisects the short arcs

representative of the mesial and distal contact

areas.


Mandibular Canine

Crown is narrower mesiodistally than

maxillary. Though it is just as long mostly.

Root is usually somewhat shorter.

Cusp is not as well developed.

Cusp ridges are thinner labiolingually.


Labial Aspect

Mesiodistal dimension lesser by about 1mm.

Crown appears longer.

Mesial outline of crown is nearly straight with

that of root.

Mesial contact area is near the mesioincisal

angle.

DCA more incisal than maxillary canine.


Lingual Aspect

Lingual surface is flatter.

Cingulum smooth and poorly developed.

Marginal ridges less distinct.

Lingual portion of root is narrower.


Mesial Aspect

Less curvature labially on the crown with very little

curvature directly above the cervical line (as a rule

less than .5 mm).

Cingulum not as pronounced.

Incisal portion of crown thinner labiolingually

therefore cusp appears more pointed.

Cervical line curves more towards incisal portion.

Developmental depression on root is more

pronounced and sometimes quite deep.


Incisal Aspect

Mesiodistal dimension is less than

Labiolingual dimension but the outline of

mesial surface is less curved.


REFERENCES

Wheeler’s. Textbook of Dental Anatomy,

Physiology and occlusion. Ninth edition.


The Permanent Canines, Maxillary and Mandibular Permanent... · Maxillary canine The labial and lingual outline is a series of curves except for the angle made by the tip of cusp.

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