Dental Anatomy
Permanent Mandibular Incisors
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Content:
1- Permanent Mandibular Central Incisor.
2- Permanent Mandibular lateral Incisor.
3-Some differences between maxillary
and mandibular central incisors.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Mandibular incisors are four in number;
2 central incisors (right & left) and 2
lateral incisors (right & left).
Characteristic features of
Permenant Mandibular Incisors:
1. The mandibular incisors have
smaller mesio-distal dimensions
than any of the other teeth.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
2. The contact areas are near the incisal
ridges mesially and distally.
3. The lingual surface is relatively
smooth and featureless with the
marginal ridges and the cingulum being
not well developed.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
4. The labial surface inclined lingually so
that the incisal ridge is lingual to a line
bisecting the root.
5. The incisal surfaces of these teeth
show a labial inclination in contrast to
those of the maxillary incisors which
have a lingual inclination.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Permanent Mandibular Central
Incisor
Principal identifying features:
1. It is the smallest tooth in the
permanent dentition.
2. The incisal ridge is lingually
inclined.
3. Well-defined distal longitudinal
groove is seen on the root.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Labial Aspect
1. The incisal ridge is straight and nearly
at a right angle to the long axis of the
tooth.
2. The disto-incisal angle is more
rounded than the mesio-incisal angle.
3. The contact areas are incisal to the
junction between incisal and middle
thirds of the crown.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
4. The mesial and distal root
outlines are straight; with a distally
curved apex.
D M
5. The labial surface of the crown is
smooth; being flat at the incisal third
and becoming more convex as it goes
cervically.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Lingual Aspect
1. The lingual surface of the crown is
smooth with very slight concavity at the
incisal third .
2. No developmental grooves are found
near the cingulum.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Mesial Aspect
1. The labial outline above the cervical
curvature is straight.
2. The lingual outline shows a shallow
concavity ending to the blunt incisal
ridge which is lingual to a line bisecting
the root.
3. The curvature of the cervical line
goes incisally about one-third the
length of the crown.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
4. The mesial surface of the root
showed a broad development
depression for most of the root and
this become deeper at the junction of
the middle and apical third.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Distal Aspect
1. The cervical lines curvature is less
than that mesially.
2. The developmental depression in the
root is more marked than that on the
mesial side with a deeper and more
well-defined developmental groove in
its center.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Incisal Aspect
1. The mesial half of the crown is
almost identical to the distal half
(bilateral symmetry).
2. The incisal edge is at a right angle
to a line bisecting the crown labio-
lingually.
(Mark of identification).
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
3. At the incisal third, the labial
surface of the crown is broad and
slightly convex,
and the lingual surface is slightly
concave.
4. More of the labial surface may be
seen than of the lingual
surface from this aspect.
5. Labio-lingual diameter is greater
than mesio-distal one.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Permanent Mandibular Lateral
Incisor
Principal identifying features:
1. Slightly larger than the
mandibular central incisors with
fan shaped crown.
2. The crown is slightly longer,
but the root is considerably
longer than the mandibular
central incisors.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
3. The mesial side of the crown is longer
than the distal side, causing the incisal
ridge to slope downward in a distal
direction.
4. The distal contact area is more
towards the cervical area than
mesial contact area.
5. Faint marginal ridges but more
prominent than in mandibular
central incisors.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
6. The incisal edge is twisted distally in a
lingual direction to follow the curvature
of the lower arch.
7. There are mesial and distal
developmental depressions on
the root.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Some differences between maxillary and
mandibular central incisors:
Feature Max. Central Incisor Mand. Central Incisor
Location of Centered over the root. More lingually positioned.
the incisal ridge
Labial outline Convex cervically, slightly Slightly convex cervically,
(from mesial aspect) convex to the incisal ridge. straight to the incisal ridge.
Lingual aspect Featurefull. Featureless.
Contact areas More cervically. More incisally.
Size Larger. Smaller.
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
Thank you
Dental Anatomy lec 7
Dr. Malak Alhuwaizi
