2. MANDIBULAR INCISOR
Mandibular central incisor and lateral are similar in anatomy and complement each
other in function.
The most simple teeth in shape
Smallest teeth permanent
Central a little smaller than the Latral, Unlike the Maxillary Incisor
Crowm is a little larger than Maxillary Incisor in incisocervical and Narrow in
mesiodistal
3. MANDIBULAR CENTRAL INCISOR
Mandibular central incisors are two in number
First tooth from the midline in each lower quadrant
bite and cutting
Mesial conatact with each other and distal contact with latral incisor
They are smaller than the maxillary central incisors
erupts at the 7
Narrowest tooth mesiodistally of all permanent teeth
4. TOOTH NUMBERING SYSTEMS
Universal system
24-25
Palmer
1 1
FDI
3 1 – 4 1
3141
3.0 2.05.36.03.55.012.59.0
Curvature of
Cervical Line
M D
Labiolingual
Diameter at
Cervical Line
Labiolingual
Diameter at
Crest of Curvature
Mesiodistal
Diameter at
Cervical Line
Mesiodistal
Diameter at
Contact Area
Root
Length
Crown
Length
Average Dimensions in millimeters
5.
6. LABIAL ASPECT
The Labial surface is Convex in both Mesiodistal and Incisocervical
The H.OFC and max Convex of This surface is in cervical third
Reverse trapezoid Like rectangular
CEJ
7. LABIAL ASPECT
Mamelons are usually present on newly emerged teeth
3 Mamelons (like Maxilary incisor)
8. LABIAL ASPECT
The mesial and distal outlines is straight in the incisal third
The crown tapers to the cervical third
Contacts are well within the incisal one third
9. LABIAL ASPECT
Mesio and distoincisal angle is nearly 90 degrees
Mesioincisal Sharp than other incisor angle
It is the only incisor where both mesioincisal and distoincisal
angles are sharp and at right angles
11. LABIAL ASPECT
The tooth is so symmetrical it is difficult to tell left from right
Only difference is the mesial cervical line curve more incisally
than the distal
12. LABIAL ASPECT
H.OFC is in the incisal third and it’s in contact area
Mesial and distal contact areas are within the incisal third at roughly
the same height and it’s near to incisal edge
13. LABIAL ASPECT
Can have two shallow depressions in the incisal third
(similar to maxillary, but far less pronounced)
It’s from incisal edge to cervical third
No Imbrication Line
14. LINGUAL ASPECT
Mesial contour is like labial surface but som time it’s concave
in gingival semi
Distal contour is like labial surface
The Crown incisocervical length is more than labial surface
And CEJ is Closer to Apex
No grooves, pits or accessory ridges are present
Marginal ridge
Mesilingual and distolingual Primery Depression seen sometimes
in insical part
CEJ
15. LINGUAL ASPECT
The lingual crown surface is smooth and shallow with
a slight concavity in the middle and incisal thirds
The cingulum is convex, small and centered
H.OFC is cingulum
16. PROXIMAL ASPECT
triangle
The labial contour is so slightly curved than cervical third
The lingual contour is convex on the cingulum(1/3), concave in
the fossa(2/3)
The lingual margin is ‘S’ shaped
The cervical line on the mesial and distal surface is convex incisally
CEJ in distal Surface have lower arch
‘S’ shaped
lingual surface
Cervical line
convex incisally
17. PROXIMAL ASPECT
The facial height of contour is located in the cervical third
The lingual height of contour is located on the cingulum,
within the cervical third
Contact area is in center and in incisial third and it’s oval
18. PROXIMAL ASPECT
The incisal edge is on or lingual to the long axis of the root
The slope of the incisal edge is to Lingual(occlusion)
19. INCISAL ASPECT
The labiolingual measurement of the crown is greater than the mesiodistal measurement
rhombic(Unlike maxilary)
bilateral symmetry (Unlike maxilary)
The incisal edge or ridge is at right angles to the labiolingual root axis plane(Unlike maxilary)
Cingulum have veryfaint tendency to distal
20. ROOT
The root is single and straight
From labial or lingual view, root is generally symmetricalt,
Root and tapers gradually to a relatively sharp apex
tip may curve to the distal
wide faciolingually
Root is narrow mesiodistally, tapering gradually from
the cervical line to the apex
21. The facial and lingual sides of theroot are nearly
straight from the cervical line to the middle third
Longitudinal grove and …
cross section in CEJ and Mid
ROOT
22. In cross section at neck, outline is roughly a rectanglewith
rounded corners, but it is slightly wider at labial than at lingual
When there are root concavities present, they are reflected
as concavities in the mesial and distal outlines
The mid root cross section is similar to the cervical section,
only more ovoid
ROOT SECTION
24. MANDIBULAR LATRAL INCISOR
Mandibular latral incisors are two in number
Second tooth from the midline in each lower quadrant
bite and cutting and complements the central in function
Mesial conatact with Central Incisor and distal contact with Canine
slightly wider mesiodistally
Bilateral symmetry not seen
erupts at the 8
slightly larger in all respects than the mandibular central incisor
25. TOOTH NUMBERING SYSTEMS
Universal system
23-26
Palmer
2 2
FDI
3 2 – 4 2
3.0 2.05.86.54.05.514.09.5
Curvature of Cervical
Line
M D
Labiolingual
Diameter at
Cervical Line
Labiolingual
Diameter at
Crest of Curvature
Mesiodistal
Diameter at
Cervical Line
Mesiodistal
Diameter at
Contact Area
Root
Length
Crown
Length
Average Dimensions in millimeters
27. LABIAL ASPECT
The Labial surface is Convex in both Mesiodistal and Incisocervical
The H.OFC and max Convex of This surface is in cervical third
Reverse trapezoid Like rectangular
CEJ
minimal depressions
28. LABIAL ASPECT
Mamelons are usually present on newly emerged teeth
3 Mamelons (like Maxilary incisor)
29. LABIAL ASPECT
The cervical portion of the lingual aspect is narrower while the
incisal portion is wider. This gives the crown a more or less a fan
shaped appearance
The crown tapers to the cervical third
Contacts are well within the incisal one third
Mesial and distal contact areas are within the incisal third but
not at roughly the same height and The distal contactcervical to
the level of the mesial contact
H.OFC is in the incisal third and it’s in contact area
Contact area on distal is more cervically located than on
The mesial, thus creating a more cervically located height of
contour on distal outline
30. Incisal margin may slope slightly gingivally toward distal,
which results in a distoincisal angle that is more rounded
than same angle of central incisor
This feature creates a slightly shorter distal margin,
when compared to mesial outline
LABIAL ASPECT
31. LABIAL ASPECT
Can have two shallow depressions in the incisal third
(similar to maxillary, but far less pronounced)
It’s from incisal edge to cervical third
minimal depressions(central)
No Imbrication Line
32. LINGUAL ASPECT
not bilaterally symmetrical
Crown is tilted distally
Mesial contour is like labial surface
Distal contour is like labial surface
The Crown incisocervical length is more than labial surface
And CEJ is Closer to Apex
No grooves, pits or accessory ridges are present
Marginal ridge
Mesilingual and distolingual Primery Depression seen sometimes
in insical part
CEJ
33. LINGUAL ASPECT
The lingual crown surface is smooth and shallow with
a slight concavity in the middle and incisal thirds
The cingulum is slightly distal to the long axis of the root
,similar to the maxillary central
This makes the mesial marginal ridge longer than the distal
The cingulum is convex, small and centered
H.OFC is cingulum
Marginal ridges and lingual fossa are not conspicuous and generally smooth
35. PROXIMAL ASPECT
triangle
The labial outline in the incisal third is slightly convex and
in the middle and incisal thirds is nearly flat
The lingual contour is convex on the cingulum(1/3), concave in
the fossa(2/3)
The lingual margin is ‘S’ shaped
The cervical line on the mesial and distal surface is convex incisally
Both cervical line curvatures are slightly less than their
counterparts in the central.
CEJ in distal Surface have lower arch
‘S’ shaped
lingual surface
Cervical line
convex incisally
Central Lateral
36. PROXIMAL ASPECT
The facial height of contour is located in the cervical third
The lingual height of contour is located on the cingulum,
within the cervical third
mesial Contact area (H.ofc) is in center(labioligual) and in
Incisial third and it’s oval
Distal Contact area (H.ofc) is in central but in incisial and
medial third(only)
37. PROXIMAL ASPECT
The incisal edge is on or lingual to the long axis of the root
The slope of the incisal edge is to Lingual(occlusion)
From the mesial a distolingual twist of the incisal
edge places the distal portion more lingual
Central Lateral
38. INCISAL ASPECT
The labiolingual measurement of the crown is greater than the mesiodistal measurement
Not bilaterally symmetrical, distal is twisted (Unlike central)
The cingulum is off center to the distal
39. ROOT
The root is single and straight
Root length is normally a little greater than in central incisor
Root is also slightly thicker and wider
Not symmetricalt,Root and tapers gradually to a relatively sharp apex
tip may curve to the distal
wide faciolingually
Root is narrow mesiodistally, tapering gradually from
the cervical line to the apex.It may have a distal curvature
40. The facial and lingual sides of theroot are nearly
straight from the cervical line to the middle third
Longitudinal(distal>mesial) grove and …
Root concavities may be found on the mesial and
distal root surfaces, and if present, concavity in
distal is usually more pronounced
cross section in CEJ and Mid
ROOT
41. In cross section at neck, outline is roughly a rectanglewith
rounded corners, but it is slightly wider at labial than at lingual
When there are root concavities present, they are reflected
as concavities in the mesial and distal outlines
The mid root cross section is similar to the cervical section,
only more ovoid
ROOT SECTION
43. MANDIBULAR CENTRAL INCISOR MANDIBULAR LATERAL INCISOR
1. CROWN MORE SYMMETRICAL LESS SYMMETRICAL
2. CROWN & ROOT ARE SHORTER CROWN & ROOT ARE LONGER
3. CINGULUM CENTERED CINGULUM DISTAL TO CENTRE
4. NO DISTOLINGUAL TWIST OF INCISAL
EDGE
DISTOLINGUAL TWIST OF INCISAL EDGE
5. MARGINAL RIDGES NOT PROMINENT LONGER MESIAL MARGINAL RIDGE
44. MAXILLARY INCISORS MANDIBULAR INCISORS
LABIAL
1. CROWN MESIODISTALLY WIDER & LESS
SYMMETRICAL
CROWN IS LONG, NARROW & MORE
SYMMETRICAL
2. DISTOINCISAL ANGLES MORE
ROUNDED
MESIOINCISAL SHARP, & DISTOINCISAL
ANGLES ARE SLIGHTLY ROUNDED
3. SHALLOW LABIAL DEPRESSIONS ARE
COMMONLY PRESENT
NOT PRESENT
LINGUAL
1. LARGER CINGULUM SMALLER CINGULUM
2. DEEPER LINGUAL FOSSA SHALLOW FOSSA
3. SOMETIMES LINGUAL PITS PRESENT LINGUAL PITS ABSENT
4. PROMINENT MARGINAL RIDGES LINGUAL SURFACE SMOOTH, less MARGINAL
RIDGES
5 CINGULUM SLIGHTLY DISTAL CENTRAL ALMOST SYMMETRICAL
PROXIMAL
1. CINGULUM IS PROMINENT VERY SMALL CINGULUM
2. INCISAL EDGE LABIAL TO ROOT AXIS INCISAL EDGE LINGUAL TO ROOT AXIS
45. INCISAL
1. CROWNS ARE WIDER MESIODISTALLY THAN
FACILINGUALLY
CROWNS WIDER FACIOLINGUALLY THAN
MESIODISTALLY
2. INCISAL EDGE LABIAL TO ROOT AXIS INCISAL EDGE LINGUAL TO ROOT AXIS
3. CINGULUM OF CI IS SLIGHTLY DISTAL
CINGULUM OF LI IS IN CENTRE
CINGULUM OF CI IS CENTERED
CINGULUM OF LI IS SLIGHTLY DISTAL
4. LABIAL SURFACE OF LI IS SLIGHTLY
CONVEX
CENTRAL & LATERALS HAVE ALMOST
FLAT LABIAL SURFACES AT INCISAL &
MIDDLE 3rd.
