The chart, letter by letter
Right and left are the child's own. FDI numbers primary teeth in quadrants 5 to 8, and Palmer letters them A to E from the midline, so a Palmer A is a central incisor, not the Universal A.
| Letter | FDI | Palmer | Tooth | Erupts, about | Shed, about |
|---|---|---|---|---|---|
| A | 55 | URE | upper right primary second molar | 25 to 33 months | 10 to 12 years |
| B | 54 | URD | upper right primary first molar | 13 to 19 months | 9 to 11 years |
| C | 53 | URC | upper right primary canine | 16 to 22 months | 10 to 12 years |
| D | 52 | URB | upper right primary lateral incisor | 9 to 13 months | 7 to 8 years |
| E | 51 | URA | upper right primary central incisor | 8 to 12 months | 6 to 7 years |
| F | 61 | ULA | upper left primary central incisor | 8 to 12 months | 6 to 7 years |
| G | 62 | ULB | upper left primary lateral incisor | 9 to 13 months | 7 to 8 years |
| H | 63 | ULC | upper left primary canine | 16 to 22 months | 10 to 12 years |
| I | 64 | ULD | upper left primary first molar | 13 to 19 months | 9 to 11 years |
| J | 65 | ULE | upper left primary second molar | 25 to 33 months | 10 to 12 years |
| K | 75 | LLE | lower left primary second molar | 23 to 31 months | 10 to 12 years |
| L | 74 | LLD | lower left primary first molar | 14 to 18 months | 9 to 11 years |
| M | 73 | LLC | lower left primary canine | 17 to 23 months | 9 to 12 years |
| N | 72 | LLB | lower left primary lateral incisor | 10 to 16 months | 7 to 8 years |
| O | 71 | LLA | lower left primary central incisor | 6 to 10 months | 6 to 7 years |
| P | 81 | LRA | lower right primary central incisor | 6 to 10 months | 6 to 7 years |
| Q | 82 | LRB | lower right primary lateral incisor | 10 to 16 months | 7 to 8 years |
| R | 83 | LRC | lower right primary canine | 17 to 23 months | 9 to 12 years |
| S | 84 | LRD | lower right primary first molar | 14 to 18 months | 9 to 11 years |
| T | 85 | LRE | lower right primary second molar | 23 to 31 months | 10 to 12 years |
A quick way to remember the letters
Learn the four corners and the middle. A, J, K and T are the four second molars, one at each end of each arch. E and F are the two upper central incisors, and O and P the two lower central incisors. The canines are C, H, M and R. From any of those you can count to the tooth you need. The same path means a letter sits roughly above or below the permanent tooth that will replace it: primary second molar A is followed by permanent second premolar 4, not by a molar.
How primary teeth are called chairside
A letter on its own is easy to mishear, so operators usually say "letter A" or "tooth A", and many use a phonetic word for letters that sound alike, such as B, D, E, P and T. You will hear callouts such as "letter K, occlusal sealant", "letter S, pulpotomy" and "letter S, stainless steel crown". The findings that come up most on children are sealants, stainless steel crowns, pulpotomies and decay on the molars. A pulpotomy on a primary molar is usually followed by a stainless steel crown on the same tooth, and both are charted as separate findings.
Worked example: a mixed dentition
An eight year old has the permanent first molars and incisors, but the primary canines and molars are still in place. The operator calls "number 3, occlusal sealant", then "letter A, DO caries", then "letter B, MO composite". Number 3 is the permanent upper right first molar, which erupted behind the primary teeth at about six. Letter A is the primary upper right second molar, just in front of it, and letter B the primary first molar in front of that. Each is charted in its own system on the same chart. When A is shed at about ten to twelve, the permanent second premolar, number 4, takes its place.
Common mistakes
- Charting a primary tooth with a permanent number, or the reverse, in a mixed dentition.
- Counting primary teeth from the midline, as Palmer does, when your chart uses Universal letters from A.
- Expecting primary premolars. The teeth behind the primary canine are molars.
- Mishearing letters that rhyme. If B, D, E or T is unclear, ask at a natural pause.
- Charting a sealant on a front tooth. Sealants go on the pits and fissures of molars.
Practise with the primary teeth category in dental charting practice by category, or start with the free daily drill. For the permanent teeth and FDI conversions, see Universal, FDI and Palmer numbering.
Sources
Checked against these sources on 26 September 2026. Conventions differ between schools, offices and clinics; where yours differ, follow your program.
- American Dental Association, Universal Numbering System. The US system that letters the primary teeth A to T along the same path as the permanent teeth 1 to 32.
- American Dental Association, primary teeth eruption chart. The approximate eruption and shedding ages in the table. Individual children vary by months either way.
- ISO 3950, Dentistry: designation system for teeth and areas of the oral cavity. The FDI two digit notation, with quadrants 5 to 8 for primary teeth.