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Clinical Prof.Nattaya Asawaworarit
Clinical Prof.Nattaya Asawaworarit
DENTAL ANATOMY (DTMS 233,DTMS234,DTMS235)
The Form & Function of the Teeth
Introduction to
Dental Anatomy
Course Objectives (DTMS 233)
At the completion of this course, students will be able to: 1. Name the teeth and their structures, parts of a tooth, tooth surfaces and supporting tissues
2.Identify teeth in: -Palmer’s notation system -Two-digit system (the FDI World Dental Federation notation) -Universal numbering system
Course Objectives (DTMS 233)
3.Indicate the general eruption sequence of teeth
4.Demonstrate the knowledge of the morphology of each tooth
Course Contents (DTMS 233)
1. Nomenclature:Teeth and their structures, parts of a tooth, tooth surfaces and supporting structures
2.Tooth Identification systems: -Palmer’s notation system -Two-digit system -Universal numbering system
Department of Masticatory Science
3.Tooth morphology and Tooth Alignment
Course Contents
4. Chronology of Tooth Eruption
The knowledge of DA is most important to the dentist since without a complete understanding of the form of human teeth, no dentist can operate on these tissues and restore them to their correct contour and proper function.
Example of lab.& clin.practice related to DA. To carve the filling material after filling the cavity.
Fixed bridge restoration
Dental Anatomy Laboratory DTMS 234, DTMS 235
Course Objectives :
Cognitive and psychomotor skills related to the morphology and functional relationships of human dentition
(Dentition=natural teeth in the jaw)
1.Lab:Nomenclature
(name,terminology)
Course Contents (DTMS 234,235)
2. Lab. : Tooth Identification
Course Contents
Primary teeth
: Tooth Identification
Course Contents
Permanent teeth
One of the most important educational tasks for acquiring visual discrimination skills is learning to distinguish the “ideal” from its clinical important deviation from normal. The traditional method is to examine preserved human teeth
3. Practice: Wax Tooth Carving
Course Contents
Permanent teeth
Practically all teeth are aligned in their arches with varying degrees of inclination of their axial centers.
Maxilla and upper teeth as seen from anterior and lateral aspects showing average arrangement of teeth.
(more detail, later)
Mandibular teeth as seen from anterior aspects showing arrangement of teeth relative to alveolar bone.
The positioning of axial center(a) of the molar is such that the crown is inclined toward the lingual.
The hypothetical relation btw correct crown contour and gingival health. The outer and inner surfaces of the crowns contain just enough convexity so that the food is deflected away from the gingival sulcus.
Incorrect crown contour, the surfaces are too flat for the adjacent soft tissues. The result of this form is that microbial plaque and food debris become lodged in the ging.sulcus.
Incorrect crown contour, the surfaces are too ‘bulbous’ for the adjacent soft tissues. The microbial plaque and food debris tend to accumulate under the pronounced contour.
The proper relation btw crown contour and the thickness of soft tissues. This results in a continuity of crown form & tissue form and creates a sulcus area less likely to accumulate microbial plaque and food debris. .
Too flat crown contour
Evaluation:
• Practicing grade • Wax carving examination • T. ident. examination
Function of Human Teeth
2. Pronunciation
3. Facial appearance
(mastication= the process of biting or chewing food)
Form is made by Function
Form & Function of our teeth are result of Evolution
Evolutionary patterns of Tooth:
In Shape;
All the teeth are the same in form and type
Evolutionary patterns of Tooth:
In Shape
Comprised of diff types,or classes of teeth to perform diff functions in the mastication process
Evolutionary patterns of Tooth:
In Set:
1.Monophyodont
There is only one set of teeth in their lifetime.
Beluga whale
Evolutionary patterns of Tooth:
In Set:
2.Diphyodont
Mammals usually have 2 sets of teeth
Evolutionary patterns of Tooth:
3.Polyphyodont
In Set:
The dentitions that have an endless succession of teeth
Alligator
Evolutionary patterns of Tooth:
3. Polyphyodont
The teeth of kangaroo,a rare example of a polyphyodont mammal
Polyphyodont (Multiple sets of teeth )
Evolutionary patterns of Tooth:
In its Attachment to the jaw:
Pleurodont Having the teeth attached by their sides to the inner side of the jaw
Acrodont
Attached on the top of the jaw bone without socket
fauna
Fauna
Animals collectively: especially, the animal of a particular region or time
The American Heritage Dictionary
Thecodont
Tooth attachment where the tooth is set in the socket in the bone
Evolutionary patterns of Tooth:
mammals
How to
Identify
a tooth?.....
To identify a tooth:
1. Set trait (Primary or Permanent)
2. Class trait (I,C,P,M)
3.Arch trait (Mx or Md)
4.Type trait ลกัษณะเฉพาะของ แต่ละซ่ี (1st,2nd or 3rd)
5. Right or Left?
NOMENCLATURE
SET OF TEETH
SET NUMBER erupt shed
PRIMARY 20 ½ - 2½
yrs
6-12yrs
SECONDARY 32 6-18 yrs ?
PRIMARY T.
DECIDUOUS T.
MILKY T.
1.Permanent Dentition Each Q contains 8 teeth of differing type and function.
@2 Incisors are clostest to the midline,(cutting, and incising) @1 Canine,the 3rd tooth from the midline,(tearing, piercing and holding),also called Cuspid @2 Premolars,the 4th& 5th teeth from the midline, (tearing,holding& grinding),also called Bicuspid @3 Molars,they are termed 1st ,2nd, 3rd molars
Classification of Teeth:
central incisor lateral incisor caninee 1st premolar
3rd molar 2nd molar 1st molar
2nd premolar
1 1 2 2 3
molar premolar bicuspid
canine cuspid
central lateral
incisors
Classification of Teeth:
2.Deciduous Dentition Each Q contains 5 teeth of all of which have a function similar to permanent teeth
@2 Incisors,they are termed central& lateral incisors @1 Canine @2 Molars,they are termed 1st ,2ndmolar
CLASS OF TEETH TOOTH
ANTERIOR TEETH
ฟันตดั (Incisor) ฟันเขีย้ว (Canine, Cuspid)
I C
POSTERIOR TEETH
ฟันกรามน้อย (Premolar, Bicuspid) ฟันกราม (Molar)
P
M
DENTAL FORMULA PERMANENT DENTITION
ICPM = 2123
PRIMARY DENTITION
ICM = 212
PRIMARY DENTITION
DENTAL FORMULA
PERMANENT DENTITION
DENTAL FORMULA
Dentition Periods: Man has 2 dentitions, but 3 periods of dentition:
1. Primary Dentition Period :the period which only deciduous teeth are present(6months-6yrs of age)
2.Mixed Dentition Period :the period which both deciduous and permanent teeth are present(6-12yrs)
3.Permanent Dentition Period : only permanent teeth are present (approx. 12 yrs through the rest of life)
DENTITION AGE
1. PRIMARY D. 6 MONTHS - 6YRS
2. MIXED D. 6-12 YEARS
3. PERMANENT D. 12 YEARS
Dentition Periods:
The natural process by which deci roots are”melted away”to allow for exfoliation,is termed
resorption
For a permanent tooth to erupt in to a space where a deciduous tooth is located,
the deciduous tooth must first be shed or exfoliated.
The permanent teeth
that replaced
exfoliated deci teeth in
the mouth are called
succedaneous teeth (means”succeeding”
deciduous teeth)
The permanent T, which are
also“succedaneous” teeth include
incisors and canines (replace their deciduous
counterparts) , and premolars which replace
deciduous molars
The only permanent T, which are
not“succedaneous” are Molars
All“succedaneous” teeth
are permanent T,
All The permanent T are not succedaneous T
1 2
4 3
Teeth are arranged in 2 arches( upper & lower). The teeth in the U/- arch are termed maxillary. The teeth in the -/L arch are termed mandibular.
The imaginary vertical line which divides each arch is the midline (mid-sagittal plane)
The 2 portions of each arch divided by the midline are termed quadrants
There are 4 Q in the mouth as a whole:
Type trait:
ANTERIOR
POSTERIOR TEETH
Canine (Cuspid) Premolar
(Bicuspi
Lateral Central
ฟันกรามน้อยบนซ้ายซี่ที่หน่ึง
ฟันกรามแท้ล่างซ้ายซี่ที่สอง (Mandibular left permanent
2nd molar)
Mandibular right permanent lateral
incisor Maxillary right permanent third molar
(Maxillary left permanent1st
premolar)
ฟันเขีย้วนํา้นมล่างขวา
(Mandibular right deciduous canine)
Maxillary left deciduous canine Mandibular right deciduous 1st molar
ฟันกรามนํา้นมบนขวาซี่ที่สอง (Maxillary right deciduous 2nd molar)
Tooth Numbering Systems
In clinical practice, some “shorthand” of tooth notation is necessary for recording data. Several systems are in use around the world, but only a few are considered here.
PALMER’s system
INTERNATIONAL SYSTEM (TWO- DIGIT)
AMERICAN OR UNIVERSAL SYSTEM
(Numbering system)
The symbolic system is most often referred to as the Palmer notation system
A= central incisor B= lateral incisor C= canine D= 1st molar E= 2nd molar
the Palmer notation system
For the permanent dentition beginning with the central incisors, the teeth are numbered 1 through 8 in each Q.
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
However, because of difficulties with keyboard notation of the symbolic notation system, the ADA in 1968 officially recommended the “universal” numbering system.
The universal numbering system for the primary dentition uses uppercase letters for each of the primary teeth:
• For the maxillary teeth, beginning with the right 2nd molar, letters A through J, • For the mandibular teeth, letters K through T, from the left mandibular 2nd molar
In the universal notation system for the permanent dentition
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17
• The maxillary teeth are numbered from 1 through 16, beginning with the right 3rd molar.
• Beginning with the mandibular left 3rd molar, the teeth are numbered 17 through 32.
Thus the right mandibular 3rd molar is #32
The universal numberring system is acceptable to computer language, whereas the Palmer notation is generally incompatible with computers and word processing systems. Each tooth in the universal system is designated with a unique number, which leads to less confusion than with the Palmer notation.
Two-digit system proposed by Federation Dentaire Internationale (FDI) has been adopted by the WHO and accepted by other organizations
For the permanent teeth:
Upper Right Upper Left
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
Lower Right Lower Left
Two-digit system
For the permanent teeth:
Upper Right Upper Left
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
Lower Right Lower Left
The 1st digit indicates the Q (1-4 for permanent), The 2nd digit indicates the tooth within a Q. (1-8 for permanent teeth,1-5 for primary teeth)
For the primary teeth:
Upper Right Upper Left
55 54 53 52 51 61 62 63 64 65
85 84 83 82 81 71 72 73 74 75
Lower Right Lower Left
5 indicates U/ Rt side, 6 indicates U/ Lt side, 7 indicates /L Lt side, 8 indicates /L Rt side
• ASH MM, Ramfjord S. Occlusion 4th.ed. Philadephia : Saunders, 1995
• Dawson PE. Evaluation,Diagnosis,and Treatment of Occlusal Problems. St.Louis : Mosby, 1974.
• Junge D. Oral Sensorimotor Function.Medico Dental Media Interntl Inc.1998
• Okeson JP. Management of Temporomandibular Disorders and Occlusion, 6th.ed. St Louis : Mosby year book,2008.
• Mc Neill C (ed.) Science and Practice of Occlusion. Chicago : Quintessence, 1997
• Mohl ND, Zarb GA, Carlsson G E, Rugh JA. A Textbook of Occlusion. Chicago: Quintessence, 1988.
• Rufenacht C R. Fundamental of Esthetics. Chicago : Quintessence, 1990.
• Smukler H. Equilibration in the Natural and Restored Dentition. Chicato: Quintessence, 1991.
Reference
