# Tooth E: Primary Upper Right Central Incisor

> In the Universal Numbering System, primary tooth E is the primary upper right central incisor (primary maxillary right central incisor). Its FDI (ISO 3950) designation is 51 and its Palmer designation is A in the upper right quadrant. It is a incisor in the upper arch with typically 1 root.

URL: https://dentovio.com/tools/tooth-numbering-chart/tooth-e

Markdown: https://dentovio.com/tools/tooth-numbering-chart/tooth-e/index.html.md

Last verified: 2026-07-08

Neutral tooth-designation reference only; not clinical, diagnostic, or treatment advice. Root counts describe typical primary-tooth morphology and vary between individuals.

## Direct answer

- Which baby tooth is letter E? In the Universal Numbering System, primary tooth E is the primary upper right central incisor (primary maxillary right central incisor). Its FDI (ISO 3950) designation is 51 and its Palmer designation is A in the upper right quadrant. It is a incisor in the upper arch with typically 1 root.
- Universal letter: E
- FDI / ISO 3950 designation: 51
- Palmer designation: A UR
- Plain-language name: Primary Upper Right Central Incisor
- Anatomical name: Primary Maxillary Right Central Incisor
- Quadrant: Upper Right
- Arch and side: upper, right
- Type: incisor
- Typical roots: 1

## Conversion table

| System | Designation |
| --- | --- |
| Universal Numbering System | E |
| FDI / ISO 3950 | 51 |
| Palmer notation | A UR |
| Tooth name | Primary Upper Right Central Incisor |

## Search terms

- which baby tooth is letter e?
- tooth E
- tooth letter E
- baby tooth E
- primary tooth E
- primary upper right central incisor
- primary maxillary right central incisor
- fdi 51
- palmer A
- upper right tooth 1
- upper right incisor

## Sources

- `TOOTH-1` American Dental Association — Universal Numbering System. <https://www.ada.org/publications/ada-news/2020/november/how-to-count-teeth-numbering-systems>
- `TOOTH-2` ISO 3950:2016 — Dentistry, designation system for teeth and areas of the oral cavity (FDI two-digit). <https://www.iso.org/standard/68292.html>
- `TOOTH-3` FDI World Dental Federation — two-digit notation. <https://www.fdiworlddental.org/>

## Related

- [Full tooth numbering chart](https://dentovio.com/tools/tooth-numbering-chart/index.html.md)
- [FDI to Universal converter](https://dentovio.com/tools/fdi-to-universal-converter/index.html.md)
- [Palmer notation converter](https://dentovio.com/tools/palmer-notation-converter/index.html.md)
- [Previous tooth: Tooth D: Primary Upper Right Lateral Incisor](https://dentovio.com/tools/tooth-numbering-chart/tooth-d/index.html.md)
- [Next tooth: Tooth F: Primary Upper Left Central Incisor](https://dentovio.com/tools/tooth-numbering-chart/tooth-f/index.html.md)