1. Human
DentitionIntroduction
:Dental Anatomy Includes
1- Nomenclature & terminology.
2- The external morphology and internal
composition of individual teeth.
3-How tooth form serves its function.
4- The relationship of teeth to each
other and to the jaw bones.
6. Quadrants:
right & left quadrants
Maxillary right
and left.
Mandibular right
and left.
Right Left
Right Left
4 Quadrants
7. Functions of Teeth
1- Mastication:
teeth are designed to perform this function.
Incisors Canine Premolars Molars
Chisel like
Cutting or
incising
Wedge like
Cutting
and
tearing
At least two
projections
(cusps).
Tearing and
grinding
Multiple
projections
(cusps)
Grinding
8. 4- Growth of jaws:
The teeth play a role in the growth of the jaws in some
periods of life.
2- Appearance:
- Well arranged clean
teeth with proper
alignment give nice
appearance to the face. –
Teeth give support to the
facial expressions.
3- Speech:
for clear pronunciation and
production of sound.
16. The permanent teeth are numbered
from 1-8 on each side from the midline.
Upper right Upper left
8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8
8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8
Lower right Lower left
Horizontal and vertical lines = symbol for the quadrant
It represents the four quadrants of the dentition
as if you are facing the patient.
In upper right In upper left
In lower right In lower left
18. The deciduous teeth are lettered
from A-E on each side from the midline
Upper right Upper left
E D C B A A B C D E
E D C B A A B C D E
Lower right Lower left
19. 2-The International Numbering System
“FDI” Federation Dentaire International
(the two digit system)
The teeth are designated by using two-digits:
a. The first digit of the code is located at the left side of
the number and indicates the quadrant:
In permanent dentition In deciduous dentition
U.R. 1 2 U.L. U.R. 5 6 U.L
L.R. 4 3 L. L. L.R. 8 7 L.L.
21. Permanent teeth
18 17 16 15 14 13 12 11 21 22 23 24 25 26 27 28
48 47 46 45 44 43 42 41 31 32 33 34 35 36 37 38
b- The second digit is located at the right side of the number
and indicates the number of the tooth in the quadrant.
The two digits should be pronounced separately.
Second Digit = Tooth number in the quadrant
22. For Primary Teeth
5 6
78
First Digit = quadrant
5 6
78
51
52
53
54
55
61
62
63
64
65
71 72
73
74
75
8182
84
83
85
2-International
System
(Two Digit System)
“FDI”
Federation Dentaire
International
First Digit = quadrant
23. Primary Teeth
55 54 53 52 51 61 62 63 64 65
85 84 83 82 81 71 72 73 74 75
First Digit = quadrant
Second Digit = Tooth number in the quadrant
5 6
78
For Primary Teeth
32. Surfaces of teeth are identified by
the relationship to
surrounding orofacial structures
Each tooth
has
Five
surfaces:
1.Facial
2.Lingual,
3.Mesial, and
4. Distal (proximal)
5.Functioning surf.
(Incisal) occlusal,
33. FACIAL SURFACE
any surface on the outside
(towards the face)
1.LABIAL is facial
surface of the
anterior teeth
(green),
2. BUCCAL is the
facial surface
of the
posterior teeth
(blue).
38. :Line angle
It is formed by the junction
of two surfaces
and its name is derived
from both surfaces
:Point angle
It is formed by the junction
of three surfaces
and its name is derived
from these surfaces.
Line and Point Angles
43. Anatomical Landmarks
of the Crown
Developmental data:
Lobe:
• It is one of the primary
centers of calcification and
growth formed during the
crown development.
• Each tooth begins to
develop from four lobes or
more.
•The pulp chamber has pulp
horns corresponding to
these lobes.
44. A- Crown Elevations:
They are three small
rounded projections
of enamel present in
the incisal third of
newly erupted
incisors
It is the bulge on
the cervical third
of lingual surface
of the crown in
anterior teeth
1-Mamelons 2-Cingulum 3-Cusps
They are pyramidal
projections on the
incisal portion of the
canine and on the
occlusal surfaces of the
premolars and molars
45. 4-Tubercle
It is a small elevation produced by
excessive formation of enamel.
Tubercle is noticed at :
•the palatal surface of E & 6
•sometimes at the lingual surface of
incisors over the cingulum.
N.B. Tubercle differs from cusp , it is
formed of enamel only while cusp is
formed of pulp horn covered by dentin
and enamel.
46. Ridge or elevation
of enamel forming
the margin of the
surface of a tooth;
• on mesial /distal
margins of lingual
surfaces anterior
teeth.
• mesial & distal
margins of occlusal
surfaces posterior
teeth
5-Ridges
•Linear ridges:
Elevated portions
of tooth run in a
line named for
their location
•Cervical
•Incisal
•Labial
•Buccal
•Lingual
Marginal
Triangular
Linear
Transverse Ridge
Oblique Ridge
47. •Small , irregularly placed
auxiliary grooves.
•Branches from developmental grooves.
•They do not denote union of primary
lobes.
•The third molars followed by second
permanent molars are characterized by
high number of supplemental grooves.
B-Crown Depressions
•Lingual
fossa
•triangular
fossae
•Central
fossa
1-Developmental
grooves:
Shallow grooves that
separate cusps or primary
parts of teeth
Linear Depressions Irregular Depressions
1-Fossa
Depression or concavity
2- Supplemental
grooves:
48. 3- Fissures
• Found in the bottom of
developmental grooves.
•Result from incomplete union of
the primary lobes.
•Represent a fault in enamel.
Linear Depressions Irregular Depressions
2- PITS:
•b- FAULTY PIT:
• Develop as a result
• of incomplete formation of
enamel.
• It is located at the end of
the buccal developmental
grooves of the lower molars or
palatal developmental
grooves of the upper molars.
49. Dental Formula: Permanent
Teeth
A shorthand way of indicating the
number and relative position of teeth
– Written as ratio of upper to lower teeth for
the mouth
– Primary: 2I (incisors), 1C (canine), 2M
(molars)
– Permanent: 2I, 1C, 2PM (premolars), 3M
2I 1C 2PM 3M
X 2 (32 teeth)
2I 1C 2PM 3M
