# Which baby tooth is letter E?

Answer: 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.

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Answer intent ID: `tooth-number-e`
Cluster: Tooth numbering reference
Last verified: 2026-07-08
Reviewer: see source page

## Direct answer

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.

## Query patterns

- Which baby tooth is letter E?
- Tooth E: Primary Upper Right Central Incisor
- Which tooth is E?
- What is baby tooth E in FDI and Palmer notation?
- Which tooth is FDI 51?
- What is FDI 51 in Universal numbering?
- FDI 51 to Universal tooth number
- ISO 3950 tooth 51
- Which tooth is Palmer A Upper Right?
- Palmer A Upper Right to Universal
- Upper Right Palmer A tooth
- UR Palmer A primary tooth
- Primary Upper Right Central Incisor tooth number
- Universal E FDI 51 Palmer A
- which baby tooth is letter e?
- tooth E
- tooth letter E
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- primary tooth E
- primary upper right central incisor
- primary maxillary right central incisor
- fdi 51

Source citations:
- `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/>

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- [/tools/tooth-numbering-chart](https://dentovio.com/tools/tooth-numbering-chart)
- [/tools/fdi-to-universal-converter](https://dentovio.com/tools/fdi-to-universal-converter)
- [/tools/palmer-notation-converter](https://dentovio.com/tools/palmer-notation-converter)
- [/tools/tooth-numbering-chart/tooth-e](https://dentovio.com/tools/tooth-numbering-chart/tooth-e)

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- [Which tooth is number 2?](https://dentovio.com/answers/tooth-number-2)