How do dentists number teeth?

Your dentist says you need work done on your #17 tooth, and you feel too embarrassed to ask what exactly that means.

Well, you can stop wondering, because we have your numbers — when it comes to teeth, anyhow.

How are teeth numbered?

If your dentist is using the most common Universal Numbering System (the Adult version), numbering starts with the tooth all the way at the back, on the upper row, on the right. That tooth number 1 is your third molar (aka a wisdom tooth).

An adult typically has 16 teeth on both top and lower decks, and they’re numbered as shown below.

Reading the tooth chart

Here’s the dental numbering key:

1. 3rd Molar (wisdom tooth)
2. 2nd Molar (12-year molar)
3. 1st Molar (6-year molar)
4. 2nd Bicuspid (second premolar)
5. 1st Bicuspid (first premolar)
6. Cuspid (canine/eye tooth)
7. Lateral incisor
8. Central incisor (left front tooth)
9. Central incisor (right front tooth)
10. Lateral incisor
11. Cuspid (canine/eye tooth)
12. 1st Bicuspid (first premolar)
13. 2nd Bicuspid (second premolar)
14. 1st Molar (6-year molar)
15. 2nd Molar (12-year molar)
16. 3rd Molar (wisdom tooth)

17. 3rd Molar (wisdom tooth)
18. 2nd Molar (12-yr molar)
19. 1st Molar (6-yr molar)
20. 2nd Bicuspid (second premolar)
21. 1st Bicuspid (first 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 (first premolar)
29. 2nd Bicuspid (second premolar)
30. 1st Molar (6-year molar)
31. 2nd Molar (12-year molar)
32. 3rd Molar (wisdom tooth)

Baby teeth basics

In kids (who still have their primary/baby teeth), the teeth are either numbered as above with the addition of a lower case “d” after the number (which stands for deciduous).

More commonly, however, the 20 baby teeth are lettered (in the same sequence as above), going from A through T.

For another version of the tooth-by-tooth explanation, check out this Universal Numbering System chart of Designations for Teeth, which is part of the American Dental Association’s PDF of Dental Abbreviations, Symbols and Acronyms.