Mandibular central and lateral incisor

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2. MANDIBULAR CENTRAL
INCISOR
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4. 1/11/2024 Free Template from
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INTRODUCTION
 MANDIBULAR INCISORS are 4 in number, two in each quadrant.
 The incisors present in adjacent to the midline k/a CENTRAL
INCISORS while those distal to them k/a LATERAL INCISOR.
 Mandibular Central incisor are some what smaller than lateral
incisor.

5. PECULIAR FEATURES
• It is the smallest tooth in both permanent and primary
dentition
• The tooth is bilaterally symmetrical so it is very difficult to
tell which side it is
• It is smallest mesio-distally by dimension than any other
tooth in dentition
• The incisal ridge is at right angle to tooth central axis
which is a distinguishing feature between mandibular
central and lateral incisor
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6. TRAITS
A trait is distinguishing characteristic ,quality ,pecularity ,or attribute.
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7. TRAITS
SET
TRAITS
ARCH
TRAITS
CLASS
TRAITS
TYPE
TRAITS
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8. 1. SET TRAITS
• Also known as “DENTITION TRAITS”.
• Distinguish the teeth in primary dentition from
permanent dentition.
• For eg.in primary dentition set of 20 teeth is
present whereas in permanent dentition 32 teeth is
present.
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9. 2. ARCH TRAITS
• Distinguish the maxillary arch teeth from
mandibular arch teeth.
• For eg. maxillary has ‘U’ shaped arch and
in mandible its ‘V’ shape arch.
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10. 3. CLASS TRAITS
• It distinguish four categories of teeth found in both
arches.
• Eg:- incisors have crown compressed labiolingually for
efficient cutting.
• Canine have single pointed cusp for piercing food.
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11. • Premolars have two or three cusp for
shearing and grinding.
• Molars have three to five somewhat
flattened cusps, ideally suited for grinding
food morsels
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12. 4. TYPE TRAITS
• Differentiate teeth within one class.
• Eg:- between central and lateral incisors
• Or between 1st and 2nd pre molars.
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13. CHRONOLOGY
FIRST
EVIDENCE
OF
CALCIFICAT
ION
ENAMEL
COMPLETE
D
ERRUPTION ROOT
COMPLETE
D
3 TO 4
MONTHS
4 TO 5
YEARS
6 TO 7
YEARS
9 YEARS
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14. Measurement Table
Cervic
o –
incisal
length
of
crown
Length
of the
root
M-D
diamet
er of
the
crown
M-D
diamet
er of
crown
at
cervix
Labio-
Lingual
diamet
er of
the
crown
Labio-
Lingual
diamet
er of
the
crown
at
cervix
Curvat
ure of
cervica
l line-
Mesial
Curvat
ure of
cervica
l line-
Distal
Dimen
sion
sugges
ted for
carving
9.5 12.5 5.0 3.5 6.0 5.3 3.0 2.0
In millimeters
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15. BRIEF STUDY
• LABIAL ASPECT
• LINGUAL ASPECT
• PROXIMAL ASPECT
• INCISAL ASPECT
• ROOT 15

16. LABIAL SURFACE
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17. • The labial surface is triangular in
shape with base towards incisal
edge and apex towards cervical line
• The incisor third is flat and middle
and cervical third is slightly convex
• The mesial and distal outline is
nearly straight and crown tapers
from contact areas towards cervical
part
• The incisal edge is straight and is at
right angle to long axis of tooth
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18. • Contact areas : both Mesially
and distally, it is at incisor
third
• Proximoincisal angle : both
mesioincisal and distoincisal
angles are sharp and right
angle
Root:
 The mesial and distal outlines
are straight towards apical
portion of root.
 The apical third of the root
terminates in a small ,pointed
taper, in most cases curving
distally. 18

19. LINGUAL SURFACE
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20. • Out line is same as that of labial
surface but with lingual tapering
• Slightly concave from middle and
incisal third and relatively smooth
with shallow lingual fosse
• Cingulum is very small slightly
convex and centrally placed in
cervical third area
• Marginal ridges are very much
inconspicuous
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21. • The lingual surface becomes
flat & then convex as
progression is made from the
incisal third to the cervical
third.
• No other tooth in the mouth,
except the mandibular lateral
incisors, shows so few
developmental lines & grooves.
• The outlines & surfaces of the
mandibular incisors are
regular & symmetrical.
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22. MESIAL ASPECT
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23. • the crown is wedge shape
• the labio-lingual dimension is more in
comparison with mesio-distal dimension
• the labial outline is straight above the
cervical curvature sloping rapidly from
the crest of contour to incisal edge
• The incisal ridge is rounded or worn flat,
& its centre is usually & its centre is
usually lingual to the centre of the root.
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24. • the lingual outline is straight from the
incisal edge to lingual fosse where it
becomes slightly concave and then
again at cingulum it becomes slightly
convex
• the incisal edge is lingually placed in
relation with central axis of tooth
• cervical line curves convexly about
one third the length of crown (3mm.)
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25. Root
 The root outlines from the lingual aspect are
straight with the crown outline from the cervical
line, keeping the root diameter uniform through
the cervical third & part of middle third.
 Outline begins to taper in the middle third areas,
tapering rapidly in the apical third to either a
bluntly rounded or a pointed root end.
 Most of the root have developmental depression
for most of the root length.
 Depression are deeper at the junction of the
middle & apical third. 25

26. DISTAL SURFACE
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27. • The features are almost similar as
mesial aspect
• the cervical line convexity is less
towards the incisal edge in
comparison with mesial surface
• The incisal edge is rounded in
young teeth where as in older
individual it is flat
• Developmental depression is more
marked.
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28. INCISAL SURFACE
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29. • mesial half is almost similar to distal
half. labial surface is wider
compared to lingual surface
• labiolingual dimension is greater
than mesiodistal dimension
 the labial surface is broad and flat & tendency towards
convexity at incisal third in comparison with cervical third
where tendency is towards concavity.
 the incisal edge is at right angle to line bisecting the crown
labio -lingually.
 When seen from incisally more of the labial surface is seen
than lingual surface.
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30. ROOT
• The root is very narrow and
slender and is 12.5 mm long
• The mesial and distal outline
is straight and within the
confines of crown and it is
evenly tapering towards
apex
• The facial and lingual out
line is straight up to middlle
third then it curves rapidly
towards apex
• The labiol-ingual dimension
is more as in crown then 30

31. MANDIBULAR LATERAL
INCISOR
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32.  it is the second mandibular tooth from the median line, right
or left.
 It resemble mandibular central incisor.
 Two incisors operate as a team in dental arch, so their
functional forms are related.
 Shape is uniform compared with other teeth.
 Rarely it will have a labial & lingual root division in the
cervical third.
 More commonly they have two canals in single root.
 Mandibular lateral incisors is somewhat larger.
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33. Surface Anatomy of Permanent Teeth
I
I
C
P
P
M
M
I, for incisor
C, for canine
P, for premolar
M, for molar

34. 34

35. •Enamel organ appearance.
•Beginning of calcification.
•Crown completed.
•Eruption.
•Root completed.
Chronology:

36. Measurement Table
Cervic
o –
incisal
length
of
crown
Lengt
h of
the
root
M-D
diamet
er of
the
crown
M-D
diamet
er of
crown
at
cervix
Labio-
Lingu
al
diamet
er of
the
crown
Labio-
Lingu
al
diamet
er of
the
crown
at
cervix
Curvat
ure of
cervic
al line-
Mesial
Curvat
ure of
cervic
al line-
Distal
Dimension
suggested
for carving
9.5 14.0 5.5 4.0 6.5 5.8 3.0 2.0
In millimeters
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37. LABIAL SURFACE
&
LINGUAL SURFACE
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38.  Labial & lingual aspects show
the added fraction approximately
1mm of crown diameter
mesiodistally.
 Mesial side of crown is longer
than the distal side, causing the
incisal ridge to slope down in a
distal direction.
 Distal contact area is more
towards the cervical than mesial
contact area. 38

39. • The distoincisal angle is more rounded than the
mesioincisal angle. this helps to distinguish rights from
the lefts prior to attrition.
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40. • As seen from the lingual and incisal views, the small
smooth cingulum lies slightly distal to the axis line of the
root similar to maxillary central incisor, making the
mesial marginal ridge slightly longer than the distal
marginal ridge.

41. • Root appears very narrow
mesiodistally and tapers
gradually from the
cervical line towards the
apex which may curve
slightly distally.
• The lingual surface of the
root convex,smooth and
narrower on the lingual
than labial sides.
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42. MESIAL SURFACE
&
DISTAL SURFACE
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43. MESIAL DISTAL 43

44. • The incisal edge is on or lingual to the mid-root axis. the
distolingual twist of the incisal ridge places the incisal distal
portion of the ridge somewhat more lingual than on the mesial.
• Mesially the cervical line has deep curvature[2mm].extending
incisally over one fourth of the crown length. the curvature
averaged 0.6 mm greater on the mesial surface than distal
surface.
• The labial crest is near the cervical line in the cervical third, the
lingual crest is on the cingulum.
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45. ROOTS:-
The root outline is nearly straight from the
cervical line to the middle third. then it
tapers.
There is longitudinal depression on the
mesial surfaces of the root.
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46. INCISAL SURFACE
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47.  Crown is broader faciolingually than mesio-
distally[by 0.4mm]
 Incisal edge not follow a straight line
mesiodistally , but rather it has a
distolingual twist: that is the distal half of
the incisal edge is bent lingually so that the
distolingual is more lingual in position than
the mesioincisal angle.

48.  So the twist of the incisal edge correspond to
the curvature of the mandibular dental arch- a
tooth on the right side of the arch is twisted
clockwise :one on the left is twisted
counterclockwise.
 Cingulum is slightly off center to the distal.
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49. Lateral incisor
Distinguish features between mandibular central
and lateral incisor
Central incisor
 More symmetrical
 Smaller overall and shorter root
 Crown is 0.6mm shorter, root is
0.9 mm shorter in same mouth
 .
 Labial and lingual view-
o Same level contacts
o Crown not bent distally on root
o No distal side bulge on crown.
 Less symmetrical[labial, lingual,
incisal views]
o Crown larger overall[especially
mesiodistallyby 0.4mm]with longer
root [0.9mm longer]
 Labial and lingual view-
o Lower distal contact.
o Crown tipped distally on root.
o Distal side bulge on crown.
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50. Central incisor Lateral incisor
 Incisal and lingual view-
o Cingulum distal to
center.
o Longer mesial marginal
ridge.
o Distolingual twist of
incisal edge
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Incisal and lingual view-
oCingulum centered.
oSame length marginal
ridges
oNo distolingual twist of
incisal edge

51. CLINICAL CONSIDERATION
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Root length: 14 mm
Root depressions/furrows: Both mesial and
distal with deeper distal depression
CEJ: Curves incisally 2–3 mm
Cervical area: May have shallow concavity

52. Summary of the Mandibular Lateral Incisor
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Labial Surface. The characteristics of
this surface are:
• An incisal edge that declines toward the distal
• A mesial surface that tapers gradually toward the
cervix
• A distal side that is slightly convex, tapering
toward the cervix.
• A sharp mesial incisal angle; a rounded distal
incisal angle
• Mesial and distal contact areas at the junction of
the incisal edge and the mesial or distal side

53. Lingual Surface. The characteristics of this surface
are:• An outline that is the reverse of the labial side.
• Cingulum, fosse, and ridges that appear the same as
those on the central incisor.
• Proximal Surfaces. The characteristics of these
surfaces are:
• Root depressions on the mesial and distal surfaces; the
distal depression is deeper.
• All other characteristics that are the same as those
pertaining to the central incisor.
• Incisal View. The characteristics of this view are:
• An incisal edge that curves toward the distal and inward
toward the lingual.
• A cingulum that is distally displaced
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mesial distal

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55. SUMMARY
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Mandibular incisors assist the maxillary
incisors in biting and cutting food.
From the labial view, both mandibular
incisors are small, narrow teeth with
a straight incisal edge and tapering
mesial and distal sides. The mandibular
central incisor is the smallest tooth in the
dentition.

56. THANK YOU
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