This document describes the anatomical features and morphology of canine teeth. It discusses the key identifying characteristics, chronology of development, and variations seen in both maxillary and mandibular canines. Some of the main points covered include: - Canines are the longest and thickest rooted teeth that help support the facial muscles and ensure normal facial expression. - Maxillary canines have more prominent cusps and roots than mandibular canines. - Development begins around ages 4-5 months with eruption around ages 11-12 years for maxillary canines and 9-10 years for mandibular canines. - Variations can include irregularly curved or bifurcated roots and variations in

1. CANINES
36
Maxillary Canine
Principal Identifying Features
 The “single” members of the dental arches.
 The most stable teeth in the dental arches.
 Their roots are the longest (16.2 mm) and thickest “labio-lingually”.
 Well anchored in the alveolar bone last teeth to be lost.
 They are referred to as the “corner stones” of the dental arches- help
to support the facial musculature.
 Both maxillary and mandibular canines have the canine eminence
which is the bone ridge over the labial portions of the roots.
 Function :
a) Anchorage in the bone
b) Cosmetic value.
c) Ensures normal facial expression at the corners of the mouth.
Chronology
First evidence of calcification 4-5 m.
Crown completed 6-7 y.
Eruption 11-12 y
Root completion 13-15 y

2. CANINES
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Labial aspect
 Geometric out line
Trapezoidal.
 The mesial outline
Convex from the cervix to the center of the mesial contact
area.
 The distal outline
Usually concave between the cervical line and the distal
contact area.
 Contact areas
Mesially: at the junction of middle and incisal thirds
Distally: is usually at the center of the middle third of the crown.
 The cusp:
The cusp tip is on a line with the center of the root. The cusp has a
mesial slope and a distal slope, the mesial slope being the shorter of
the two. Both slopes show a tendency toward concavity
 Surface description
 The labial ridge:
The middle labial lobe shows much greater development than the
other lobes. This produces a ridge on the labial surface of the crown.
 The labial surface of the crown is smooth, with shallow
depressions mesially and distally, dividing the three labial lobes.
 Cervical line
Convex root wise.
 The root

3. CANINES
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Appears slender, conical in form with a bluntly pointed apex. Mostly
curved distally in the apical third.
The labial surface of the root is smooth and convex at all points
Lingual Aspect
 The crown and root are narrower lingually than labially.
 The cingulum is large and pointed like a small cusp
 Strongly developed marginal ridges:
 Well-developed lingual ridge is seen that is
confluent with the cusp tip; this extends to a point
near the cingulum.
 Shallow concavities are evident between this ridge
and the marginal ridges. They are called mesial and
distal lingual fossae
 The lingual portion of the root of is narrower than the labial portion.
Mesial aspect
 Greater labiolingual measurement than any of the other
anterior teeth
 The crown is wedge-shaped, the greatest measurement
being at the cervical third and the wedge point being
represented by the tip of the cusp.
 Labial outline is convex with the crest of curvature at
the cervical third
 The lingual outline is convex line describing the
cingulum, which convexity straightens out as the
middle third is reached, becoming convex again in the
incisal third
 A line bisecting the cusp is labial to a line bisecting the root

4. CANINES
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 Cervical outline: curved incisally
 The outline of the root from this aspect is conical, with a tapered or
bluntly pointed apex with a shallow developmental depression.
Distal Aspect
The same form as the mesial aspect, with the following
variations:
 the cervical line exhibits less curvature
 the distal marginal ridge is heavier and more irregular
in outline;
 The developmental depression on the distal side of the
root is deeper.
Incisal Aspect
 Diamond in shape
 The labiolingual dimension is greater than the mesiodistal.
 The labial surface wider than the lingual
surface
 The tip of the cusp is labial to the center of
the crown labiolingually and mesial to the
center mesiodistally.
 The labial ridge is very noticeable labially
from the incisal aspect.
 The cingulum development makes up the cervical third of the crown
lingually.

5. CANINES
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Variations and Anomalies:
a) Crown form does not vary widely, although the sharpness of the
cusp tip has considerable range.
b) b. On rare occasions, the lingual surface may exhibit a tubercle
which is located near the most incisal level of the cingulum. When
a tubercle is present, a lingual pit is often associated with it.
c) c. Root form is subject to variations. There may be several
curvatures along its length. If curved in the apical third, the
deflection is most commonly to the distal.
d) d. Since the maxillary canine normally erupts after the maxillary
premolars, its space is sometimes partially closed. It may then
erupt well to the labial or lingual of the other teeth, or not erupt at
all, in which case it is considered to be impacted.

6. CANINES
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Mandibular Canine
Principal Identifying Features
 The mandibular canine crown is narrower mesiodistally than that of
the maxillary canine
 -The root is somewhat shorter. The labiolingual diameter of crown
and root is smaller
 -The lingual surface of the crown is smoother, with less cingulum
development and less bulk to the marginal ridges.
 -The cusp of the mandibular canine is not as well developed as that of
the maxillary canine, and the cusp ridges are thinner labiolingually.
Usually the cusp tip lies lingual to the line, as with the mandibular
incisors.
Chronology
First evidence of calcification 4-5 m.
Crown completed 6-7 y.
Eruption 9-10 y
Root completion 12-14 y

7. CANINES
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Labial Aspect
 Less mesio-distal dimensions than those of the maxillary canine.
 The crowns of the mandibular canines appear longer; the effect of
greater length is increased by:
a) The narrowness of the crown mesiodistally
b) The height of the contact areas above the cervix.
 The mesial outline
Nearly straight with the mesial outline of the root, with the mesial
contact area being.
 The distal outline
Convex inciso-cervical.
 Contact areas
Mesially: near the mesioincisal angle “at the
middle of the incisal third”.
Distally: at the junction between middle and incisal
thirds.
 The cusp:
The cusp angle is on a line with the center of the
root, as on the maxillary canine. The mesial cusp ridge is shorter.
 The cervical line:
Semicircular curvature apically.
 The root
The mandibular canine root is shorter by l or 2 mm on average than
that of the maxillary canine, and its apical end is more sharply
pointed.

8. CANINES
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Lingual Aspect
 The lingual surface of the crown of the mandibular
canine is flatter, simulating the lingual surfaces of
mandibular incisors
 The lingual surface of the crown is smooth and regular;
the cingulum is smooth and poorly developed. The
marginal ridges are less distinct, the lingual ridge is
shallow except toward the cusp tip, where it is raised.
 The lingual portion of the root is narrower relatively
than that of the maxillary canine.
Mesial Aspect
 The mandibular canine has less curved labial outline while
the lingual outline of the crown is curved in the same
manner as that of the maxillary canine; as the cingulum is
not as pronounced, and the incisal portion of the crown is
thinner labiolingually, which allows the cusp to appear
more pointed.
 The tip of the cusp is more nearly lingual over the root
 The cervical line curves more toward the incisal portion
 The roots of the two canines are similar but more pointed
root tip on the mandibular canine.
 The developmental depression mesially on the root of the mandibular
canine is more pronounced

9. CANINES
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Distal Aspect
Little difference from the distal aspect can be seen
between mandibular and maxillary canines; contact
area position, less curvature of the cervical line, and
deeper depression on the root surface.
Incisal Aspect
 The outlines of the crowns of mandibular and maxillary canines from
the incisal aspect are often similar
 The main differences to be noted are as follows:
 The mesiodistal dimension of the mandibular
canine is less than the labiolingual dimension.
A similarity is evident in this.
 The cusp tip and mesial cusp ridge are more
likely to be inclined in a lingual direction in the
mandibular canine.
Variations and Anomalies
a) Crown form is not greatly variable.
b) Irregularly curved roots ate occasionally seen, and bifurcated roots,
with labial and lingual branches, are also possible.