lec. 2
Numbering systems:
1. Palmer notation system:
It represents the four quadrants of the dentition as if you are facing the patient. In
upper right upper left
lower right lower left
A. Permanent teeth:
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
B. Deciduous teeth:
E D C B A A B C D E
E D C B A A B C D E
2. Universal notation system:
A. Permanent teeth:
Maxillary
1 2 3 4 5 6 7 8 9 0 11 12 13 14 15 16
32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17
Mandibular
B. Deciduous teeth:
A B C D E F G H I J
T S R Q P O N M L K
Examples:
# 13 : Permanent Maxillary Left Second Premolar.
# S : Deciduous Mandibular Right First Molar.
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.
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.
Permanent dentition
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
Primary Teeth
55 54 53 52 51 61 62 63 64 65
85 84 83 82 81 71 72 73 74 75
Crown and root:
Each tooth has a crown and root. The crown is covered with enamel; the root is covered with cementum. The enamel and the cementum are joined with each others at the cemento-enamel junction or the cervical line.
The major bulk of the tooth is the dentin which lies beneath the enamel and the cementum. The enamel, dentin and cementum representing the hard tissue of the tooth.
Dental pulp:
Is the soft tissue of the tooth and present in the pulp chamber and pulp canals.
Pulp chamber:
Is the part of dental pulp in the crown.
Pulp canal:
Is the part of dental pulp in the root.
Anatomical crown:
Is the part of the crown which is covered with enamel.
Clinical crown:
Is the portion of the tooth which is visible in the mouth, in a healthy person the clinical crown is smaller than the anatomical crown.
The number of roots:
1. Single root: in all anterior teeth, Mandibular premolars and maxillary second premolars.
2. Two roots: in Mandibular molars and maxillary second premolars.
3. Three roots: in maxillary molars.
Surfaces and ridges:
The crowns of incisors and canines have 4 surfaces and a ridge, while the crown of premolars and molars have 5 surfaces. These surfaces are:
1. Labial surface: is the surface which is toward the lips in incisors and canines.
2. Buccal surface: is the surface toward the cheek in premolars and molars. The Buccal and labial surfaces are termed Facial surface.
3. Lingual surface: is the surface which is facing the tongue in all teeth.
4. Occlusal surface: is the surface of the posterior teeth coming in contact with the teeth in the apposite jaw during closing the mouth. In anterior teeth, the surface is called (incisal ridge).
5. Proximal surfaces: is the surface of the tooth which is facing towards adjacent teeth in the same dental arch, its divided into:
A. Mesial surface: is the surface which is facing towards the mid line.
B. Distal surface: is the surface which is facing away from the midline.
All the teeth have their mesial surface touching distal surface of the adjacent teeth except the maxillary and Mandibular central incisors.
Division of the crown and roots into thirds:
The crown and root are divided into thirds according to its position on the tooth to facilitate the study of tooth anatomy.
Line angle:
it is formed by the junction of two surfaces and gets its name from these surfaces
e.g. mesio-labial line angle.
Point angle:
is formed by the junction of three surfaces and gets its name from these surfaces
e.g. mesio-lingo-incisal point.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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