Universal Numbering System

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title: "Universal Numbering System" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["dentistry-terminology", "human-mouth-anatomy"] description: "American dental notation system" topic_path: "science/biology" source: "https://en.wikipedia.org/wiki/Universal_Numbering_System" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary American dental notation system ::

::callout[type=note] the dental notation system ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/6/6c/Universal_Numbering_System.svg" caption="Universal numbering system. This is a dental practitioner view, so tooth number 1, the rear upper tooth on the patient's right, appears on the left of the chart."] ::

The Universal Numbering System, sometimes called the American system, is a dental notation system commonly used in the United States.

Most of the rest of the world uses the FDI World Dental Federation notation, accepted as an international standard by the International Standards Organization as ISO 3950. However, dentists in the United Kingdom commonly still use the older Palmer notation despite the difficulty in representing its graphical components in computerized (non-handwritten) records.

Left and right

Dental charts are normally arranged from the viewpoint of a dental practitioner facing a patient. The patient's right side appears on the left side of the chart, and the patient's left side appears on the right side of the chart.

The labels "right" and "left" on the charts in this article correspond to the patient's right and left, respectively.

Universal numbering system

Although it is named the "universal numbering system", it is also called the "American system" as it is only used in the United States. The uppercase letters A through T are used for primary teeth and the numbers 1 - 32 are used for permanent teeth. The tooth designated "1" is the maxillary right third molar ("wisdom tooth") and the count continues along the upper teeth to the left side. Then the count begins at the mandibular left third molar, designated number 17, and continues along the bottom teeth to the right side. Each tooth has a unique number or letter, allowing for easier use on keyboards.

::data[format=table title="Universal numbering system table"]

Permanent dentition	upper right	upper left	lower right	lower left	Primary dentition	upper right	upper left	lower right	lower left	Alternate system for primary dentition	upper right	upper left	lower right	lower left
1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
32	31	30	29	28	27	26	25	24	23	22	21	20	19	18
			A	B	C	D	E	F	G	H	I	J
			T	S	R	Q	P	O	N	M	L	K
			1d	2d	3d	4d	5d	6d	7d	8d	9d	10d
			20d	19d	18d	17d	16d	15d	14d	13d	12d	11d
::

Tooth numbering

Permanent teeth and their assigned numbers (Universal Tooth Numbering System)

Upper right | 3rd molar (wisdom tooth) | 2nd molar (12-yr molar) | 1st molar (6-yr molar) | 2nd bicuspid (2nd premolar) | 1st bicuspid (1st premolar) | Cuspid (canine/eye tooth) | Lateral incisor | Central incisor Upper left | Central incisor | Lateral incisor | Cuspid (canine/eye tooth) | 1st bicuspid (1st premolar) | 2nd bicuspid (2nd premolar) | 1st molar (6-yr molar) | 2nd molar (12-yr molar) | 3rd molar (wisdom tooth) Lower left | 3rd molar (wisdom tooth) | 2nd molar (12-yr molar) | 1st molar (6-yr molar) | 2nd bicuspid (2nd premolar) | 1st bicuspid (1st premolar) | Cuspid (canine/eye tooth) | Lateral incisor | Central incisor Lower right | Central incisor | Lateral incisor | Cuspid (canine/eye tooth) | 1st bicuspid (1st premolar) | 2nd bicuspid (2nd premolar) | 1st molar (6-yr molar) | 2nd molar (12-yr molar) | 3rd molar (wisdom tooth)

References

References

1. "Tooth Numbering Systems". American Dental Association.
2. American Dental Association. (August 2022). "Universal Tooth Designation System".
3. [http://standardsforum.com/iso-3950/ ISO 3950 Updated – Dentistry Designation System]
4. "Histology: A Text and Atlas by Michael H. Ross • Wojciech Pawlina".

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::