Overview

The American Dental Association (ADA.org) recognizes two major systems used for numbering teeth. The Universal/National System is used primarily in the United States and the International Standards Organization System is used in most other countries.

The Universal/National System for permanent (adult) dentition (1-32) includes:

Tooth # 1 is the patient's upper right molar and follows around the upper arch to the upper left third molar (16), descending to the lower left third molar (17) and follows around the lower arch to the lower right third molar (32).

The Universal/National System order for the primary (baby) dentition is the same as described for the permanent dentition, however, the primary teeth are designated by upper case letters A through T, with A being the patient's upper right second primary molar and T being the lower right second primary molar.

Source: American Dental Association "Current Dental Terminology Third Edition (CDT-3)" (c) 1999.


                             Upper Left                                                     Upper Right
                             Lower Left                                                     Lower Right

The Permanent Arch

Upper (Maxilla)
RightLeft
Lower (Mandible)

1. 3rd Molar (wisdom tooth)
2. 2nd Molar (12-yr molar)
3. 1st Molar (6-yr molar)
4. 2nd Bicuspid (2nd premolar)
5. 1st Bicuspid (1st premolar)
6. Cuspid (canine/eye tooth)
7. Lateral incisor
8. Central incisor
9. Central incisor
10. Lateral incisor
11. Cuspid (canine/eye tooth)
12. 1st Bicuspid (1st premolar)
13. 2nd Bicuspid (2nd premolar)
14. 1st Molar (6-yr molar)
15. 2nd Molar (12-yr molar)
16. 3rd Molar (wisdom tooth)
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17. 3rd Molar (wisdom tooth)
18. 2nd Molar (12-yr molar)
19. 1st Molar (6-yr molar)
20. 2nd Bicuspid (2nd premolar)
21. 1st Bicuspid (1st premolar)
22. Cuspid (canine/eye tooth)
23. Lateral incisor
24. Central incisor
25. Central incisor
26. Lateral incisor
27. Cuspid (canine/eye tooth)
28. 1st Bicuspid (1st premolar)
29. 2nd Bicuspid (2nd premolar)
30. 1st Molar (6-yr molar)
31. 2nd Molar (12-yr molar)
32. 3rd Molar (wisdom tooth)