Dental anatomy intro

8/4/2019 Dental anatomy intro

http://slidepdf.com/reader/full/dental-anatomy-intro 1/62

Human DentitionIntroduction

:Dental Anatomy Includes

1- Nomenclature & terminology.

2- The external morphology and internalcomposition of individual teeth.

3-How tooth form serves its function.

4- The relationship of teeth to each

other and to the jaw bones.



Dental Anatomy Nomenclature

The Jaws & Dental Arches



A. The maxilla is

two bones formingthe upper jaw;

they are rigidlyattached to the skull.

B. The mandible isa horse-shoe

shaped bone whicharticulates with theskull by way of thetemporo-mandibular

joint the TMJ.

The Jaws and Dental Arches



Quadrants:right & left quadrants

Maxillary right

and left.

Mandibular right

and left.

Right Left

Right LeftQuadrants



Functions of Teeth1- Mastication:

teeth are designed to perform this function.Incisors Canine Premolars Molars

hisel like utting orincising

Wedge like Cutting

andtearing

At least twoprojections(cusps).

Tearing and

grinding

Multipleprojections

(cusps)Grinding



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 properalignment give niceappearance to the face. – Teeth give support to the

facial expressions.3- Speech:

for clear pronunciation and

production of sound.



Types of Teeth



Types of Teeth

Posterior Teeth

Anterior Teethfor

cutting & tearingfood



Anterior Teeth - Upper

lateral CentralIncisors

Canine



Anterior Teeth - Lower

lateral - CentralIncisorsCanine



Premolars:(in permanent only)

First premolar&

Second premolar

Upper

Lower



Molars:

First & second

Upper

Lower

Wisdom tooth =Third permanent molar



Types of Dentitions:Primary & Permanent Dentition



Types of Dentitions:I-Primary Dentition

Deciduous ,baby, milkteeth:a. Twenty ( 20)

primary teeth.b. 10 in each archc. 5 in each quadrant

In function:2 years 12 years



I-Primary Dentition



Mixed Dentition Period

6 years 12 years

Eruption

offirstpermanent

molar

Shedding

oflastprimarymolar



6 years eruption of first permanent molar



12 years Shedding of last primary molar



II-Permanent Dentition

Infunction:

12 years

through

outlife



Permanent Teeth



1.Palmer Notation System

2.Universal System

3.International FDI System

(two digit system)

Tooth Identification

Systems Numbering or Coding Systems

1 l i S



1 - 8

1 1

1-Palmer Notation System

2 3

45

6

7

8

2 3 4 5 6 7 8

1 2345

67

8

Right Leftfor Permanent Teeth

8 - 1

8 - 1

1 - 8

It t th f d t f th d titi



The permanent teeth are numberedfrom 1-8 on each side from the midline.

Upper right Upper left8 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

P l N t ti S t



AB

C

D

E

Palmer Notation System

for Primary Teeth

E-A

E-A

A-E

A-E



The deciduous teeth are letteredfrom 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



Palmer Notation System

2 The International Numbering System



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.



2-International

System

(Two Digit System)“FDI” Federation Dentaire

International

111213

1415

16

17

18

21 22

232425

26

27

28

31 323334

3536

37

38

414243

444546

47

48

1 2

34

For permanent Teeth

First Digit = quadrant



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



For Primary Teeth

5 678

First Digit = quadrant 5 6

78

5152

53

54

55

6162

63

64

65

7172

73

74

75

8182

84

83

85

2-International

System

(Two Digit System)“FDI” Federation Dentaire

International

First Digit = quadrant



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



Universal

system

forPermanent

Teeth



Universal

System

for PrimaryTeeth

M & M



Macro & Micro-anatomyof Teeth

crown

neck

root



Surrounding Bone:Crypt developing tooth

Socket erupted tooth root



Anatomical Crown & Clinical Crown



Single-rooted Multi-rooted



Micro-anatomy of Teeth

Pulp Cavity



Pulp Cavity

1-Coronal pulp:•Pulp chamber

•Pulp horns

2-Radicular pulp:•Root canal•Apical foramen

P l C R



2-Radicular pulp:•Root canal

•Apical foramen

Pulp Cavity in Root



Surfaces

ofTeeth

Surfaces of teeth are identified by



Surfaces of teeth are identified bythe relationship to

surrounding orofacial structures

Each toothhasFive

surfaces:

1.Facial2.Lingual,

3.Mesial, and4. Distal (proximal5.Functioning surf.(Incisal) occlusal,

FACIAL SURFACE



FACIAL SURFACE any surface on the outside

(towards the face)

1.LABIAL is facialsurface of the

anterior teeth(green),2. BUCCAL is the

facial surfaceof theposterior teeth(blue).

Inter proximal



Inter-proximalsurfaces:

1.Facing towards themidline: MESIAL.

2. Facing away from the

midline: DISTAL

Surfaces in between two teeth:

LINGUAL



LINGUAL The surfaces facing the tongue

PALATAL on the maxilla.

palatal

F ti i S f



Functioning Surfaces:chewing/biting surfaces of teeth :

OCCLUSAL: chewing surfaces ofposterior teeth

INCISAL: the anteriors’

biting surface

Li d P i t A l



Line and Point AnglesDivision into Thirds



:Line angleIt is formed by the junctionof two surfaces and its name is derived

from both surfaces

:Point angle It is formed by the junctionof three surfaces

and its name is derivedfrom these surfaces.

Line and Point Angles

Li A l



Line Anglesof Anterior Teeth

Li A l



Line Anglesof Posterior Teeth

P int An l



Point AnglesMeeting of 3 surfaces

Di isi n int Thi ds



Division into Thirds

Anatomical Landmarks



Anatomical Landmarksof the Crown

Developmental data:Lobe: • It is one of the primarycenters of calcification and

growth formed during thecrown development.

• Each tooth begins to

develop from four lobes ormore.

•The pulp chamber has pulphorns corresponding to

these lobes.



Anterior teeth

premolars



Maxillary molars

Mandibular molars

A- Crown Elevations:



A Crown Elevations:

They are three smallrounded projectionsof enamel present in

the incisal third of newly erupted

incisors

It is the bulge onthe cervical thirdof lingual surfaceof the crown inanterior teeth

1-Mamelons 2-Cingulum 3-Cusps

They are pyramidalprojections on the

incisal portion of thecanine and on the

occlusal surfaces of the

premolars and molars



4-Tubercle

It is a small elevation produced byexcessive 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 isformed of enamel only while cusp is

formed of pulp horn covered by dentinand enamel.

5-Ridges



Ridge or elevation

of enamel formingthe margin of thesurface of a tooth;

• on mesial /distalmargins of lingual surfaces anteriorteeth.

• mesial & distalmargins of occlusal

surfaces posteriorteeth

5-Ridges

•Linear ridges:Elevated portionsof tooth run in aline named fortheir location

•Cervical•Incisal•Labial•Buccal

•Lingual

Marginal

Triangular

Linear

Transverse Ridge

Oblique Ridge

B-Crown Depressions



•Small , irregularly placedauxiliary grooves.

•Branches from developmental grooves.•They do not denote union of primarylobes.•The third molars followed by secondpermanent molars are characterized by

high number of supplemental grooves.

B-Crown Depressions

•Lingualfossa

•triangularfossae

•Centralfossa

1-Developmentalgrooves:

Shallow grooves thatseparate cusps or primaryparts of teeth

Linear Depressions Irregular Depressions

1-FossaDepression or concavity

2- Supplementalgrooves:

Linear Depressions Irregular Depressions



3- Fissures• Found in the bottom of

developmental grooves.•Result from incomplete union ofthe primary lobes.•Represent a fault in enamel.

p g p

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 orpalatal developmental

grooves of the upper molars.

Dental anatomy intro

Documents

Transcript of Dental anatomy intro