COLLEGE OF DENTISTRY
DENTAL MORPHOLOGY
[111 RDS]
LAB MANUAL
Dr. Mousa Abu Fadaleh
Dept Head
Dr. Saleem Shaikh
Course Director
CERTIFICATE
This is to certify that Mr.______________________________________________
Reg No.____________Has satisfactorily carried out the work in DENTAL ANATOMY as
Prescribed by College of Dentistry, Majmaah University for the year_______
Course director
A. DENTAL STRUCTURES :
1. Enamel : The hard, mineralized tissue outer most covering of the e anatomical
crown of a tooth. It is the hardest living body tissue, but is brittle, especially
when not supported by sound underlying dentin.
2. Dentin : The hard tissue which forms the main body of the tooth. It surrounds
the pulp cavity, and is covered by the enamel in the anatomical crown, and by
the cementum in the anatomical root. The dentin constitutes the bulk, or
majority, of the total tooth tissues, but because of its internal location, is not
directly visible in a normal tooth.
3. Cementum : The outermost layer of anatomical root, it is hard, bonelike tissue
which covers the dentin of the anatomical root.
4. Pulp : The living soft tissue which occupies the pulp cavity of a vital tooth. It
contains the tooth’s nutrient supply in the form of blood vessels, as well as the
nerve
supply.
SUPPORTING STRUCTURES :
1. Alveolar process (bone): The entire bony entity which surrounds and supports
all the teeth in each jaw member.
2. Alveolus (plural-alveoli): The bony socket, or portion of the alveolar process,
into which an individual tooth is set.
3. Periodontal ligament (membrane): The fibrous attachment of the tooth
(cementum) to the alveolar bone.
4. Gingiva (Plural-gingivae) : The “gum” or “gums”, or the part of the mucous
membrane that covers the alveolar processes and surrounds the necks of the
teeth.
RELATED TERMNOLOGY:
Anatomical crown : The portion of tooth which is covered by enamel.
Clinical crown : The portion of tooth which is visible in the mouth. The clinical
crown may or may not, correspond to the anatomical crown, depending on the
level of the tooth’s investing soft tissue. As can be seen from this description,
the clinical crown may be an ever changing entity throughout life, while the
anatomical crown is a constant entity.
Cervical line : The cervical line separates the anatomical crown and the
anatomical root, and is a constant entity. It also represents the cemento-enamel
junction (CEJ). Its location is in the general area of the tooth spoken of as the
neck or cervix.
A. Crown Elevations :
1.
Cusps :Cusp is an elevation or mold present on the crown of teeth which makes
up a divisional part of the occlusal surface. Cusps are seen on all posterior teeth,
and the incisal portion of canines.
2. Tubercles : Rounded or pointed projections found on the crowns of teeth. They
are also variable in size and shape, but are usually smaller than cusps. Tubercles
are often thought of as minicusps, and they are seen on the lingual surface of
maxillary teeth, especially deciduous canines and molars.
3. Cingulum (plural-cingula) : A large rounded eminence on the lingual surface
of all permanent and deciduous anterior teeth, which encompasses the entire
cervical third of the lingual surface.
4. Ridges : Linear and usually convex elevations on the surface of the crowns of
teeth, which are named according to their location.
a. Marginal ridges : The linear elevations which are convex in cross section and
are found at the mesial and distal terminations of the occlusal surface of
posterior teeth. They are also found on anterior teeth, but are less prominent.
Their location also differs, since on anterior teeth they form the lateral margins
of the lingual surface.
b. Triangular ridges : Linear ridges which descend from the tips of cusps of
posterior teeth toward the central area of the occlusal surface. In cross-section,
they are more or less triangular, hence their name.
c. Transverse ridge : The combination of two triangular ridges, which
transversely cross the occlusal surface on a posterior tooth to merge with each
other. Thus a transverse ridge is simply a union of two triangular ridges of a
posterior tooth, one from a buccal cusp and the other from a lingual cusp.
d. Oblique ridge : A special type of transverse ridge, which crosses the occlusal
surface of maxillary molars of both dentitions in an oblique direction from the
distobuccal to mesiolingual cusps.
e. Cusp ridges : Each cusp has four cusp ridges extending in different directions
(mesial, distal, facial, lingual ) from its tip. They vary in size, shape, and
sharpness.
5. Mamelons : Small, rounded projections of enamel which are found in varying
sizes and numbers on the incisal ridges of recently erupted incisors.
B. Crown Depressions :
1. Fossa (plural-fossae) : An irregular, usually rounded depression, or concavity,
on the crown of a tooth. There is normally a rather large, shallow fossa on the
lingual surface of anterior teeth, while posterior teeth exhibit two or more fossae
of varying size and shape on the occlusal surface.
2. Development (primary) groove : A groove, or line, which usually denotes the
coalescence of the primary parts, or lobes, of the crown of a tooth.
3. Supplemental (secondary) groove : An auxialliary groove which branches
from a developmental groove. Its location is not related to the junction of
primary tooth parts, and it is normally not as deep as a primary groove.
4. Pit : A small, depressed area where developmental grooves join or terminate. A
pit is usually found in the deepest portion of a fossa.
C. Miscellaneous Structures :
1. Contact area : The area on a proximal surface of the crown that contacts the
adjacent tooth in the same arch, and is thus named mesial or distal by location.
All teeth in each quadrant have two contact areas, except the most distal tooth
which, of course, has no distal contact area.
2. Lobe : One of the primary anatomical divisions of the tooth crown, usually
separated by identifiable developmental grooves.
Crest of contour [Height of curvature; Crest of curvature]:
Height of curvature in the tooth can be defined as the line encircling a tooth at
its greatest bulge to a selected path of insertion.
The heights of curvature have great functions to oral cavity
1. They allow the food to be deflected allowing proper degree of massage to
the gingiva.
2. They prevent the food of being accumulated at the tooth.
3. Holding the gingiva under definite tension.
• Primate spaces
They exist between the upper lateral incisors and the canines (present
mesial to maxillary deciduous canines) and lower canines and first deciduous
molars (present distal to mandibular deciduous canines). These spaces are also
known as anthropoid or simian spaces.
• Physiologic/developmental spaces
These spaces are present in between the primary teeth and play an important
role in the normal development of the permanent dentition. The total space
present may vary from 0 to 8 mm with an average 4 mm in the maxillary arch
and 1 to 7 mm with an average of 3 mm in the mandibular arch.
Primary Molar Relationship
The relationship of the distal surface of the maxillary and mandibular second
primary molars is one of the key factors that influences the future occlusion of
the permanent dentition.
i) Mesial step type :
The distal surface of the lower molar is more mesial to that of the upper.
Invariably it is favorable to guide the permanent molars into a class I
relationship.
ii) Distal step type :
The distal surface of the lower molar is more distal to that of the upper.
This relationship is prognostically unfavourable as it guides the permanent
molars into Class II malocclusion.
iii) Flush terminal or vertical plane type
The distal surface of the upper and lower teeth are in a straight plane
(flush) and therefore situated on the same vertical plane. Usually it is a
favorable relationship to guide the permanent molars.
iv) Anterior teeth relationship
Overbite:
It is the distance which the incisal edge of the maxillary incisors overlap
vertically past the incisal edge of the mandibular incisors. The average overbite
in the primary dentition is 2 mm
Overjet:
It is the horizontal distance between the Lingual aspect of the maxillary
incisors and the labial aspect of the mandibular incisors, when the teeth are in
centric occlusion. The average in primary dentition is 1-2 mm with a normal
range of 2-6 mm.
TOOTH NUMBERING SYSTEMS
Dental formula for permanent dentition
2
1
2
3
𝐼 = : 𝐶 = : 𝑃 = : 𝑀 = : (𝑋2 = 32 𝑡𝑜𝑡𝑎𝑙 𝑡𝑒𝑒𝑡ℎ)
2
1
2
3
Dental Formula for decidious dentition
2
1
2
𝐼 = : 𝐶 = : 𝑀 = : (𝑋2 = 20 𝑡𝑜𝑡𝑎𝑙 𝑡𝑒𝑒𝑡ℎ)
2
1
2
Tooth Numbering System
Universal System
1 2
Permanent
32 31
3 4 5 6
30 29 28 27
7
26
8 9
25 24
10
23
11 12
22 21
E
P
F
O
H
M
I
L
13 14
20 19
15 16
18 17
Decidious
A
T
B
S
C
R
D
Q
G
N
J
K
Zigmondy – Palmer Notation
Permanent
8
8
7
7
6
6
5
5
4
4
3
3
2
2
1
1
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
Decidious
E
E
D
D
C
C
B
B
A
A
A
A
B
B
C
C
D
D
E
E
12
42
11
41
21
31
22
32
23
33
24
34
Federation dentair Internationals (FDI)
Permanent
18
48
17
47
16
46
15
45
14
44
13
43
25
35
Decidious
55
85
54
84
53
83
52
82
51
81
61
71
62
72
63
73
64
74
65
75
26
36
27
37
28
38
MORPHOLOGY OF TEETH
Traits: A trait is a distinguishing characteristic, quality, peculiarity or attribute.
Set traits – distinguish teeth in the primary dentition from secondary dentition
Arch traits – distinguish maxillary form mandibular teeth
Class Traits – distinguish the four categories of teeth, namely incisors, canines,
premolars, molars
Type Traits – distinguish teeth within one class [ such as differences between
central and lateral incisors or 1st and 2nd premolars or 1st, 2nd and 3rd molars.
SUBDIVISIONS OF TOOTH AND CROWN:
DENTAL MORPHOLOGY
EVALUATION CRITERIA DURING WEEKLY PRACTICAL AND PRACTICAL
EXAM
During each practical the students will be given demonstration of carving of tooth specimen
from wax blocks. The students are required to do the same during the practical hours and
submit it for evaluation. The students are given a laboratory manual in which they have to
write in brief important points regarding the tooth they have carved. The students will also be
asked a few basic questions to assess their understanding of the subject and evaluate their
cognitive skills.
The students are then evaluated on the basis of:
Sl. No
1
2
3
4
5
6
7
8
9
Total
Criteria
Overall shape, proportions and appearance
Contact areas – shape and location
Crest of contour – shape and location
Occlusal detail
Characteristic features of the particular tooth
Finishing
Answering questions related to tooth carved
Completion of carving in stipulated time
Cleanliness of work area and maintenance of instruments
Score
5
2
2
2
1
1
4
1
2
20
During the practical exams: The students will be asked to carve a specific tooth in stipulated
time [45 minutes]. The submitted carving will be evaluated according to the criteria
mentioned above.
Assesment
Ex.NO
Carving
1
Geometric shape
2
Permanent Maxillary incisor
3
Permanent Mandibular incisor
4
Permanent Maxillary canine
5
Permanent mandibular canine
6
Permanent Maxillary premolar
7
Permanent mandibular premolar
8
Permanent Maxillary molar
9
Permanent mandibular molar
Date
Grade
Signature
Exercise 1:
Completion of carving of Geometric shape
Date
Grade
Signature
Exercise 2:
PERMANENT MAXILLARY CENTRAL INCISOR:
Dimensions
in mm
Length
of
crown
Length
of root
10.5
13.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
8.5
7.0
7.0
6.0
Description:
Carving of Incisor
Date
Grade
Signature
Exercise 3:
PERMANENT MANDIBULAR CENTRAL INCISOR
Dimensions
in mm
Length
of
crown
Length
of root
9.5
12.5
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
5.0
3.5
6.0
5.3
Description:
Date
Grade
Signature
Exercise 4:
PERMANENT MAXILLARY CANINE:
Dimensions
in mm
Length
of
crown
Length
of root
10.0
17.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
7.5
5.5
8.0
7.0
Description:
Carving of Canine
Date
Grade
Signature
Exercise 5:
PERMANENT MANDIBULAR CANINE
Dimensions
in mm
Length
of
crown
Length
of root
11.0
16.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
7.0
5.5
7.5
7.0
Description
Date
Grade
Signature
Exercise no 6:
PERMANENT MAXILLARY PREMOLAR
Dimensions
in mm
Length
of
crown
Length
of root
8.5
14.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
7.0
5.0
9.0
8.0
Description:
Carving of Premolar
Date
Grade
Signature
Exercise 7:
PERMANENT MANDIBULAR PREMOLAR
Dimensions
in mm
Length
of
crown
Length
of root
8.5
14.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
7.0
5.0
7.5
6.5
Description:
Date
Grade
Signature
Exercise 8
PERMANENT MAXILLARY MOLAR
Length
of
crown
Dimensions
in mm
7.5
Length
of root
12-B
13-L
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
10.0
8.0
11.0
10.0
Description:
Carving of Molar
Date
Grade
Signature
Exercise 9:
PERMANENT MANDIBULAR MOLAR
Dimensions
in mm
Length
of
crown
Length
of root
7.5
14.0
Mesiodistal Mesiodistal Labiolingual Labiolingual
width of
width of
width of
width of
crown
crown at
crown
crown at
cervix
cervix
11.0
9.0
10.5
9.0
Description:
Carving of Molar
Date
Grade
Signature