dental anatomy in general

1. DENTAL ANATOMY INTRODUCTION

2. Contents
• Introduction
• Jaws
• Quadrants
• Dentition
A. Crown
B. Roots
C. Surfaces
D. Line angle
E. Point angle
F. Thirds
G. Contact area
H. Crest of curvature
I. Cervical line
• Geometrical outline
• Tooth Numbering system
• Eruption Chart
• Anatomical Landmarks.

3. Introduction
• Dental Anatomy: is the study of
• development,
• morphology,
• function, and
• identity of each of the teeth in the human
dentitions,
• as well as
• the way in which the teeth relate in
• shape,
• form,
• structure,
• color,
• function to the other teeth in the same dental
arch and to the teeth in the opposing arch.

4. Jaws
• The term Mandibular refers to
• the Lower jaw, or Mandible.
• The term Maxillary refers to
• the Upper jaw, or Maxilla.
Mandible
Maxilla

5. Jaw Quadrants
• The term Median Line (Midline) refers
to
• Line pass vertically
• divide Jaws to Right and Left side.
• The term Occlusal Line refers to
• Line pass horizontally
• divide Jaws to Upper and Lower
(Maxillary and Mandibular).
Midline
Occlusal Line

6. Dentition Types
• The term Primary (Deciduous) dentition refers
to
• First set of teeth seen in the mouth.
• The term Permanent (Succedaneous) dentition
refers to
• Second set of teeth seen in the mouth
• (after shedding of primary teeth).

7. Dentition name
• The Name of Primary (Deciduous) dentition from midline is
• 1- Central Incisor.
• 2- Lateral Incisor.
• 3- Canine.
• 4- First Molar.
• 5- Second Molar.
• The Name of Permanent (Succedaneous) dentition from
midline is
• 1- Central Incisor.
• 2- Lateral Incisor.
• 3- Canine.
• 4- First Premolar.
• 5- Second Premolar.
• 6- First Molar.
• 7- Second Molar.
• 8- Third Molar.

8. Dentition number
• The number of Primary (Deciduous) dentition is:
20 teeth in a mouth.
10 teeth in a jaw
5 teeth in a quadrant.
• The number of Permanent (Succedaneous)
dentition is:
32 teeth in a mouth.
16 teeth in a jaw
8 teeth in a quadrant.

9. Dentition
• Anterior teeth are :
( in primary and permanent teeth)
1- Central incisor.
2- Lateral incisor.
3- Canine.
• Posterior teeth are:
( in Primary teeth) ( in Permanent teeth)
1- First molar. 1- First Premolar.
2- Second Molar. 2- Second Premolar.
3- Thirds Molar. 3- First Molar.
4- Second Molar.
5- Third Molar.

10. Dentition Parts
• Dentition consist of:
1.Crown : part of tooth that
covered with enamel.
2.Root : part of tooth that
covered with cementum.
Crown
Root
Root
Crown

11. Dentition Tissue
• Dentition Tissue are:
1- Enamel.
2- Dentin.
3- Cementum.
4- Pulp.
• The
fi
rst three are known as Hard tissue.
• The last as Soft tissue .

12. Pulp
• Pulp Cavity consist of:
1- Pulp chamber.
2- Pulp canal.
• The pulp tissue furnishes the blood and nerve
supply to the tooth.
•

13. Roots Number
The rootsof the teeth may be :
1- Single : One
2- Double : Two
2- Multiple : Three
• Both maxillary and mandibular anterior teeth have only
one root each.
• Mandibular
fi
rst and second premolars and the maxillary
second premolar are single rooted, but the maxillary
fi
rst
premolar has two roots in most cases, one buccal and
one lingual.
• Mandibular molars have two roots, one mesial and one
distal.
• Maxillary molars have three roots, one mesiobuccal, one
distobuccal, and one lingual.

14. Roots Furcation
Furcation : means region of roots
Con
fl
uence .
1- Bifurcation :
formed by union of two roots.
2- Trifurcation :
formed from union of three roots.

15. Roots Trunk
• Trunk : region extend from root
furcation to the cervical line.

16. Surfaces
A- in anterior teeth, surfaces are FOUR :
1- Labial Surface : Face Lip.
2- Lingual Surface : Face Tongue.
3- Mesial surface : Towards midline.
4- Distal Surface : Away from midline.
B- in posterior teeth, surfaces are FIVE :
1- Buccal Surface : Face Cheek
2- Lingual Surface : Face Tongue.
3- Mesial surface : Towards midline.
4- Distal Surface : Away from midline.
5- Occlusal Surface : The surfaces of the premolars
and molars that come in contact (occlusion) with
those in the opposite jaw during the act of closure.

17. Important notes
• Facial surface term called on Labial and Buccal
surface collectively.
• Proximal Surface term called on mesial surface
and also on distal surface.
• Palatal surface called on the Lingual surface in
upper jaw (Maxillary) only.
• There is no incisal surface in anterior teeth But
incisal Aspect (View).

18. Important note
• Aspect = View
So there are:
FIVE aspect or view in anterior teeth.
1- Labial aspect: Face Lip.
2- Lingual aspect: Face Tongue.
3- Mesial aspect: Towards midline.
4- Distal aspect: Away from midline.
FIVE aspect in posterior teeth.
1- Buccal aspect : Face Cheek
2- Lingual aspect : Face Tongue.
3- Mesial aspect : Towards midline.
4- Distal aspect : Away from midline.
5- Occlusal aspect : Towards opposite occlusal
aspect in the other jaw.

19. Line angle
* The Last letter of the
fi
rst surface should be eliminate
and put the letter O then write the second surface
with it all letters.
* in the line angle name TWO surfaces should be
mentioned.
1- Mesial (O) Or Distal (O)
2- Labial / Buccal Or Lingual
3- Incisal Or Occlusal 2
2
2
1
1
1
• Union of two surfaces.
• Nomenclature :

20. Examples :
• Mesiolabial line angle. • Linguo-occlusal line angle.

21. Point angle
* The Last letter of the
fi
rst and second surfaces
should be eliminate and put the letter O then write
the third surface with it all letters.
* in the point angle name THREE surfaces should be
mentioned.
• Union of three surfaces.
1- Mesial (O) Or Distal (O)
2- Labial / Buccal (O) Or Lingual (O)
3- Incisal Or Occlusal
1
2
3
• Nomenclature :

22. Examples :
• Mesiolinguo-incisal point angle. • Distobucco-occlusal point angle.

23. Thirds
• Each surface divide into three thirds :
In anterior teeth :
• Horizantally
1- Crown is divide into:
A- Incisal third
B- Middle third.
C- Cervical third.
2- Root is divide into:
A- Cervical third.
B- Middle third.
C- Apical third.

24. Thirds
• Each surface divide into three thirds :
In anterior teeth :
• Vertically
1- crown from ( Labial and Lingual Surface) is divide
into:
A- Mesial third
B- Middle third.
C- Distal third.
2- crown from ( Mesial and Distal Surface) is divide into:
A- Labial third
B- Middle third.
C- Lingual third.

25. Thirds
• Each surface divide into three thirds :
In anterior teeth :
• Vertically
1- Root from ( Labial and Lingual Surface) is divide
into:
A- Mesial third
B- Middle third.
C- Distal third.
2- Root from ( Mesial and Distal Surface) is divide into:
A- Labial third
B- Middle third.
C- Lingual third.
Distal
third
Middle
third
Mesial
third
Lingual
third
Middle
third
Labial
third

26. Thirds
• Each surface divide into three thirds :
In posterior teeth :
• Horizantally
1- Crown is divide into:
A- Occlusal third
B- Middle third.
C- Cervical third.
2- Root is divide into:
A- Cervical third.
B- Middle third.
C- Apical third.
Cervical third.
Middle third.
Apical third.

27. Thirds
• Each surface divide into three thirds :
In posterior teeth :
• Vertically
1- crown from ( Buccal and Lingual Surface) is divide
into:
A- Mesial third
B- Middle third.
C- Distal third.
2- crown from ( Mesial and Distal Surface) is divide into:
A- Buccal third
B- Middle third.
C- Lingual third.

28. Thirds
• Each surface divide into three thirds :
In posterior teeth :
• Vertically
1- Root from ( Buccal and Lingual Surface) is divide
into:
A- Mesial third
B- Middle third.
C- Distal third.
2- Root from ( Mesial and Distal Surface) is divide into:
A- Buccal third
B- Middle third.
C- Lingual third.
Distal
third
Middle
third
Mesial
third
Buccal
third
Middle
third
Lingual
third

29. Thirds
• Each surface divide into three thirds :
In posterior teeth :
• Occlusally
1- from Buccal to Lingual surface.
A- Buccal third
B- Middle third.
C- Lingual third.
2- From Mesial to Distal surface.
A- Mesial third
B- Middle third.
C- Distal third.
Buccal third
Middle third
Lingual third

30. Contact Area
• De
fi
ne as : The area of the mesial or distal
surface of a tooth that touches its neighbor in
the dental arch.
• Each tooth has mesial and distal contact area.
• Contact area di
ff
ers from tooth to tooth.
• Contact area become broader posteriorly.
• Contact area present on proximal surface as a
spot.
• Contact area term not used on proximal
surface as mesiodistal diameter width because
there is Lip Labially (Buccally) and tongue
lingually (No teeth present).
• In Labial, Buccal, Lingual surfaces
Contact area = Crest of curvature= height of contour
spot

31. Crest of curvature
• In mesial and distal surfaces
Crest of curvature NOT = Contact area.
• Crest of curvature = Height of contour.
• Term SHOULD used in proximal surface as
Mesiodistal width.

32. Cervical Line
• Line joins crown and root of the tooth.
• Inclination di
ff
ers from tooth surface to another.
• Become more straight when direct posteriorly.
• Cementoenamel Junction : Junction that locate
between enamel of crown and cementum of the
root.

33. Geometrical outline
• In a general way,
all aspects of each tooth crown except
the incisal or occlusal aspects may be
outlined with one of three geometric
fi
gures:
△ ، ⏢ ، ⏥ ،
Six anterior teeth, maxillary and
mandibular :
1- Triangular
A. Mesial aspect
B. Distal aspect

34. Geometrical outline
2- Trapezoidal
I. Trapezoid with longest uneven side toward occlusal or
incisal surface
A. All anterior teeth, maxillary and mandibular
1. Labial aspect
2. Lingual aspect
B. All posterior teeth
1.Buccal aspect
2.Lingual aspect
II. Trapezoid with shortest uneven side toward occlusal
surface
All maxillary posterior teeth
1. Mesial aspect
2. Distal aspect

35. Geometrical outline
3- Rhomboidal
All mandibular posterior teeth
A. Mesial aspect
B. Distal aspect

36. Tooth Numbering System
• In clinical practice some “shorthand” system of tooth nota-
tion is necessary for recording data.
1- The Universal notation system:
A- in primary teeth:
uses uppercase letters ,
Start from maxillary right second molar
letters A to maxillary left second molar J,
then from the mandibular left second molar letters K to
mandibular right second molar T .
B- in permanent teeth:
Uses numbers,
Start from maxillary right third molar number 1 to maxillary left
third molar 16,
then from mandibular left third molar 17 to mandibular right
third molar 32.
A- in primary teeth
B- in permanent teeth

37. Tooth Numbering System
2- The Zsigmondy/Palmer notation
system
Most common system,
In this system the arches are divided into four quadrants with
the entire dentition being notated.
A- in primary teeth:
uses uppercase letters ,
Start from central incisor A to third molar E in each quadrant.
B- in permanent teeth:
Uses numbers
The Zsigmondy/Palmer notation for the permanent dentition
is a four quadrant symbolic system in which, beginning with
the central incisors, the teeth are numbered 1 to third molar 8
in each quadrant.
A- in primary teeth
B- in permanent teeth

38. Tooth Numbering System
3- The Fédération Dentaire Internationale (FDI)
notation system
A two-digit system
The
fi
rst number (units) represents tooth name and the second
number (Tens) represents the quadrant.
A- in primary teeth:
Upper right quadrant begin from 51 to 55
Upper left quadrant begin from 61 to 65
Lower left quadrant begin from 71 to 75
Lower right quadrant begin from 81 to 85
B- in permanent teeth:
Upper right quadrant begin from 11 to 18
Upper left quadrant begin from 21 to 28
Lower left quadrant begin from 31 to 38
Lower right quadrant begin from 41 to 48
A- in primary teeth
B- in permanent teeth

39. Eruption Chart
• Primary teeth
Palmer notation system.
1- Lower A (6-10) month.
2- Upper A (8-12) month.
3- Upper B (9-13) month.
4- Lower B (10-16) month.
5- Upper C (16-22) month.
6- Lower C (17-23) month.
7- Upper D (13–19) (14–18) month.
8- Lower D (14-18) month.
9- Lower E (23–31) (24–30) month.
10- Upper E (25-33) month.

41. Eruption Chart
• Permanent teeth
Palmer notation system
1- Lower 6 (6-7) year.
2- Upper 6 (6–7) year.
3- Lower 1 (6-7) year.
4- Upper 1 (7-8) year.
5- Lower 2 (7-8) year.
6- Upper 2 (8-9) year.
7- Lower 3 (9–10) year.
8- Upper 4 (10-11) year.
9- Lower 4 (10–12) year.
10- Upper 5 (10-12) year.
11- Lower 5 (11-12) year.
12- Upper 3 (11-12) year.
13- Lower 7 (11-13) year.
14- Upper 7 (12-13) year.
15- Lower 8 (17-21) year.
16- Upper 8 (17-21) year.

42. Years

43. Anatomical Landmarks
• To study an individual tooth
intelligently, one should recognize all
landmarks of importance by name.
• A Cusp is an elevation or mound on
the crown portion of a tooth making
up a divisional part of the occlusal
surface.

44. Anatomical Landmarks
• A Tubercle is a smaller elevation on
some portion of the crown produced
by an extra formation of enamel.
• These are deviations from the typical
form.
Tubercle of Carabelli

45. Anatomical Landmarks
• A cingulum (Latin word for “girdle”) is
the lingual lobe of an anterior tooth.
• It makes up the bulk of the cervical
third of the lingual surface.
• Its convexity mesiodistally resembles
a girdle encircling the lingual surface
at the cervical third .

46. Anatomical Landmarks
•A Ridge is any linear elevation on the
surface of a tooth .

47. Anatomical Landmarks
•Named according to its location:
• Incisal ridge.
• Lingual ridge.
• Buccal ridge.
Lingual Lingual

48. Anatomical Landmarks
• Marginal ridges are those rounded
borders of the enamel.
• Form the mesial and distal margins of
the occlusal surfaces of premolars
and molars and the mesial and distal
margins of the lingual surfaces of the
incisors and canines .

49. Anatomical Landmarks
•Triangular ridges descend from the tips
of the cusps of molars and premolars
toward the central part of the occlusal
surfaces.
•They are so named because the slopes
of each side of the ridge are inclined to
resemble two sides of a triangle .
•They are named after the cusps to which
they belong,
for example, the triangular ridge of the
buccal cusp of the maxillary
fi
rst
premolar.

50. Anatomical Landmarks
• A transverse ridge is the union of two
triangular ridges crossing
transversely the surface of a
posterior tooth.
• When a buccal and a lingual
triangular ridge join, they form a
transverse ridge.

51. Anatomical Landmarks
•The oblique ridge is a ridge crossing
obliquely the occlusal surfaces of
maxillary molars and formed by the
union of the triangular ridge of the
distobuccal cusp and the distal cusp
ridge of the mesiolingual cusp .

52. Anatomical Landmarks
•A fossa is an irregular depression or
concavity.

53. Anatomical Landmarks
• Lingual fossae are on the lingual
surface of incisors .
•Borders of Lingual fossae :
1- Cingulum.
2- Mesial marginal ridge.
3- Distal marginal ridge.
4- Incisal ridge.

54. Anatomical Landmarks
•Central fossae are on the occlusal
surface of molars.
•They are formed by the convergence
of ridges terminating at a central point
in the bottom of the depression where
there is a junction of grooves .

55. Anatomical Landmarks
• Triangular fossae are found on molars
and premolars on the occlusal
surfaces mesial or distal to marginal
ridges.
• They are sometimes found on the
lingual surfaces of maxillary incisors
at the edge of the lingual fossae
where the marginal ridges and the
cingulum meet .

56. Anatomical Landmarks
• A sulcus is a long depression or
valley in the surface of a tooth
between ridges and cusps, the
inclines of which meet at an angle.
• A sulcus has a developmental groove
at the junction of its inclines.
• The term sulcus should not be
confused with the term groove.

57. Anatomical Landmarks
• A developmental groove is a shallow
groove or line between the primary
parts of the crown or root.
• Buccal and lingual grooves are
developmental grooves found on the
buccal and lingual surfaces of
posterior teeth

58. Anatomical Landmarks
•A Supplemental groove, less distinct,
is also a shallow linear depression on
the surface of a tooth,
• But it is supplemental to a
developmental groove and does not
mark the junction of primary parts.

59. Anatomical Landmarks
•A Transverse groove, is also a shallow
linear depression on the occlusal
surface of maxillary molars.
•Extend from central pit to the distal pit
crossing the oblique ridge.

60. Anatomical Landmarks
•Pits are small pinpoint depressions
located at the junction of
developmental grooves or at terminals
of those grooves.

61. Anatomical Landmarks
• Central pit is a term used to describe
a landmark in the central fossa of
molars where developmental grooves
join .

62. Anatomical Landmarks
• Mesial and Distal pit is a term used to
describe a landmark in the mesial
and distal triangular fossa of
premolars and molars where
developmental grooves join.

63. Anatomical Landmarks
• A mamelon is any one of the three
rounded protuberances found on the
incisal ridges of newly erupted incisor
teeth.

64. Anatomical Landmarks
•A Lobe is one of the primary sections
of formation in the development of the
crown.
•Cusps and mamelons are
representative of lobes.

65. END