The three systems in a minute
FDI (the international standard, ISO 3950) uses two digits. The first digit is the quadrant: 1 upper right, 2 upper left, 3 lower left, 4 lower right (5, 6, 7 and 8 are the same quadrants for primary teeth). The second digit counts from the midline: 1 is the central incisor, up to 8 for the third molar (1 to 5 in primary teeth). So 36 is the lower left first molar.
Universal numbers permanent teeth 1 to 32. It starts at the upper right third molar (1), runs across the upper arch to the upper left third molar (16), drops to the lower left third molar (17) and ends at the lower right third molar (32). Primary teeth use the letters A to T. FDI 36 is Universal 19.
Palmer gives the quadrant and the position from the midline: 1 to 8 for permanent teeth and A to E for primary teeth. In print the quadrant is drawn as a bracket; here it is written UR, UL, LL and LR. FDI 36 is Palmer LL 6.
FDI is used across much of the world, including in India. Universal is mainly an American system, and Palmer is also seen in the UK and in orthodontic texts. Odontra’s tooth chart uses FDI numbering.
Full reference table
Permanent teeth
| FDI | Universal | Palmer | Tooth |
|---|---|---|---|
| 11 | 8 | UR 1 | Upper right central incisor |
| 12 | 7 | UR 2 | Upper right lateral incisor |
| 13 | 6 | UR 3 | Upper right canine |
| 14 | 5 | UR 4 | Upper right first premolar |
| 15 | 4 | UR 5 | Upper right second premolar |
| 16 | 3 | UR 6 | Upper right first molar |
| 17 | 2 | UR 7 | Upper right second molar |
| 18 | 1 | UR 8 | Upper right third molar (wisdom tooth) |
| 21 | 9 | UL 1 | Upper left central incisor |
| 22 | 10 | UL 2 | Upper left lateral incisor |
| 23 | 11 | UL 3 | Upper left canine |
| 24 | 12 | UL 4 | Upper left first premolar |
| 25 | 13 | UL 5 | Upper left second premolar |
| 26 | 14 | UL 6 | Upper left first molar |
| 27 | 15 | UL 7 | Upper left second molar |
| 28 | 16 | UL 8 | Upper left third molar (wisdom tooth) |
| 31 | 24 | LL 1 | Lower left central incisor |
| 32 | 23 | LL 2 | Lower left lateral incisor |
| 33 | 22 | LL 3 | Lower left canine |
| 34 | 21 | LL 4 | Lower left first premolar |
| 35 | 20 | LL 5 | Lower left second premolar |
| 36 | 19 | LL 6 | Lower left first molar |
| 37 | 18 | LL 7 | Lower left second molar |
| 38 | 17 | LL 8 | Lower left third molar (wisdom tooth) |
| 41 | 25 | LR 1 | Lower right central incisor |
| 42 | 26 | LR 2 | Lower right lateral incisor |
| 43 | 27 | LR 3 | Lower right canine |
| 44 | 28 | LR 4 | Lower right first premolar |
| 45 | 29 | LR 5 | Lower right second premolar |
| 46 | 30 | LR 6 | Lower right first molar |
| 47 | 31 | LR 7 | Lower right second molar |
| 48 | 32 | LR 8 | Lower right third molar (wisdom tooth) |
Primary (milk) teeth
| FDI | Universal | Palmer | Tooth |
|---|---|---|---|
| 51 | E | UR A | Upper right central incisor |
| 52 | D | UR B | Upper right lateral incisor |
| 53 | C | UR C | Upper right canine |
| 54 | B | UR D | Upper right first molar |
| 55 | A | UR E | Upper right second molar |
| 61 | F | UL A | Upper left central incisor |
| 62 | G | UL B | Upper left lateral incisor |
| 63 | H | UL C | Upper left canine |
| 64 | I | UL D | Upper left first molar |
| 65 | J | UL E | Upper left second molar |
| 71 | O | LL A | Lower left central incisor |
| 72 | N | LL B | Lower left lateral incisor |
| 73 | M | LL C | Lower left canine |
| 74 | L | LL D | Lower left first molar |
| 75 | K | LL E | Lower left second molar |
| 81 | P | LR A | Lower right central incisor |
| 82 | Q | LR B | Lower right lateral incisor |
| 83 | R | LR C | Lower right canine |
| 84 | S | LR D | Lower right first molar |
| 85 | T | LR E | Lower right second molar |