FDI to Universal Numbering Converter
Convert one actual FDI permanent11–48or primary51–85to the standard USUniversal1–32/A–Tdesignation. Anatomical identification external; not treatment selection.
Description
FDI tooth codes encode quadrant and position, while Universal codes enumerate permanent teeth or letter primary teeth.
FDI tooth codes encode quadrant and position, while Universal codes enumerate permanent teeth or letter primary teeth.1, 2
An exact crosswalk changes the identifier while preserving the tooth identity. Use this tool to convert independently identified tooth identifiers between the stated notation systems.
When to use FDI to Universal Numbering Converter
Use this tool to convert independently identified tooth identifiers between the stated notation systems. Establish the qualified examination or measurement context, matching instrument/protocol edition, site order and units.
How to use FDI to Universal Numbering Converter and understand its results
- Establish the qualified examination or measurement context, matching instrument/protocol edition, site order and units.
- Enter independentlyIdentifiedFdiTooth, using the field meanings and rules below, then run the tool.
- Read result.universalTooth. Interpret each field using the units, signs and evidence rules below.
- If input validation fails, correct the reported field and run again. Before applying a successful result, check the stated reference scope, units, assumptions and any retained unknown evidence.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| independentlyIdentifiedFdiTooth | Independently identified fdi tooth | string | Required |
Enter an exact case-sensitive string for an independently identified tooth. The committed crosswalk covers 32 permanent and 20 primary teeth: FDI quadrants 1–4 with positions 1–8 and 5–8 with positions 1–5, matched to Universal 1–32 and A–T. Select the Universal value for the exact FDI token. Unrecognized, padded or supernumerary tokens fail. No tooth identification from images or anatomy occurs.
| FDI token | Universal token |
|---|---|
| 11 | 8 |
| 12 | 7 |
| 13 | 6 |
| 14 | 5 |
| 15 | 4 |
| 16 | 3 |
| 17 | 2 |
| 18 | 1 |
| 21 | 9 |
| 22 | 10 |
| 23 | 11 |
| 24 | 12 |
| 25 | 13 |
| 26 | 14 |
| 27 | 15 |
| 28 | 16 |
| 31 | 24 |
| 32 | 23 |
| 33 | 22 |
| 34 | 21 |
| 35 | 20 |
| 36 | 19 |
| 37 | 18 |
| 38 | 17 |
| 41 | 25 |
| 42 | 26 |
| 43 | 27 |
| 44 | 28 |
| 45 | 29 |
| 46 | 30 |
| 47 | 31 |
| 48 | 32 |
| 51 | E |
| 52 | D |
| 53 | C |
| 54 | B |
| 55 | A |
| 61 | F |
| 62 | G |
| 63 | H |
| 64 | I |
| 65 | J |
| 71 | O |
| 72 | N |
| 73 | M |
| 74 | L |
| 75 | K |
| 81 | P |
| 82 | Q |
| 83 | R |
| 84 | S |
| 85 | T |
result=toothMap[exactFdiToken] Apply the field units and exact ordering, boundary and evidence rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Structured result containing the calculation or selected reference fields below | object |
| result.universalTooth | Exact Universal tooth token selected from the committed crosswalk | string |
{
"input": {
"independentlyIdentifiedFdiTooth": "11"
},
"output": {
"result": {
"universalTooth": "8"
}
}
}Limitations and assumptions
An exact crosswalk changes the identifier while preserving the tooth identity. Results depend on the independently established measurement basis and the exact model assumptions above.
Every listed input requires an explicit value. Unexpected fields, incorrect value types, nonfinite numbers and sparse numeric arrays fail validation; tool-specific bounds and alignment rules apply as described above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful calculation that reports a false comparison or retains unknown evidence.
Alternative or Complementary methods
Use Universal to FDI Numbering Converter to examine a related aspect: Universal and FDI notation identify the same teeth using different code systems.
Use Palmer to FDI Numbering Converter where its separate inputs and scope apply: Palmer notation combines a quadrant with a position counted from the midline.
References
-
FDI to Universal Numbering Converter — tool.io
-
Universal Tooth Designation System — American Dental Association
Similar or alternative tools
- Universal to FDI Numbering Converter
Universal and FDI notation identify the same teeth using different code systems.
- Palmer to FDI Numbering Converter
Palmer notation combines a quadrant with a position counted from the midline.