2. Introduction Human dentition is diphyodont 2 sets of dentitions Primary/deciduous 20 teeth in total Incisors/canines/molars Smaller size Secondary/permanent 32 teeth in total Incisors/canines/premolars/molars Bigger size
4. Why 2 sets of dentitions? The jaws have to accommodate the increased number of permanent teeth and their bigger size
5. Dental formula I for incisors C for Canines PM for premolars M for molars Deciduous teeth are indicated by the letter D before the initial
6. Human dental formula Deciduous teeth DI 2/2 DC 1/1 DM 2/2 = 10 Permanent teeth I 2/2 C 1/1 PM 2/2 M 3/3 = 16 The numbers following the letter refer to the number of teeth of each type in the upper then the lower dentition for one side only
7. Quadrants Tooth-bearing region of the jaw can be divided into 4 quadrants Right maxillary (1 or 5) Left maxillary (2 or 6) Left mandibular (3 or 7) Right mandibular (4 or 8) Quadrants in permanent dentition have the numbers 1 - 4 and in deciduous have the numbers 5 - 8
10. Teeth order Each tooth in a quadrant takes a letter (A – E for deciduous) or a number (1 – 8 for permanent) indicating its order when counting from the midline 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 E D C B A A B C D E 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 E D C B A A B C D E
11. Dental nomenclature By words Set Deciduous or permanent Jaw Maxillary or mandibular Class Incisor/canine/premolar/molar Order within a class Central or lateral First/second/third Side Right or left By numbers, letters and/or symbols Palmer notation system Universal numbering system FDI numbering system
12. Palmer/Zsigmondy notation system 1 E American Dental Association in 1947 Tooth is represented by a number 1 – 8 (permanent) or a letter A – E (deciduous) Two lines; indicates which quadrant the tooth belongs to a horizontal representing the occlusal plane and a vertical representing the midline Examples: Maxillary right central incisor Mandibular left second deciduous molar E D C B A A B C D E 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 E D C B A A B C D E 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8
13. Universal numbering system Palmer – difficulty in keyboard typing ADA adopted the universal system in 1968 Uppercase letters for deciduous teeth Consecutive from A to T Following a clockwise order from maxillary right second molar to mandibular right second molar Numbers for permanent teeth Consecutive from 1 to 32 Following a clockwise order from maxillary right third molar to mandibular right third molar A B C D E F G H I J 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 T S R Q P O N M L K 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17
14. FDI numbering system Proposed by FDI & adopted by WHO Each tooth is allocated a two-digit number; the left designates the quadrant and the right designates the tooth order Examples Mandibular right permanent canine 43 Maxillary left deciduous lateral incisor 62 55 54 53 52 51 61 62 63 64 65 18 17 16 15 14 13 12 11 21 22 23 24 25 26 27 28 85 84 83 82 81 71 72 73 74 75 48 47 46 45 44 43 42 41 31 32 33 34 35 36 37 38
