Have you ever sat in the dentist chair, eager to tell him that you’ve been having a toothache in your top right molar in the back, only for him to say “Do you mean number two or three?” Or maybe while checking your teeth, you are told, “There seems to be a cavity starting on number 21.”
Human Teeth Diagram & Numbering
Dentists have developed a universal numbering system, giving teeth numbers to every tooth in the mouth. Although the system is called “universal,” the numbering system used in the United States is specific only to this country. Different numbering systems are used in different parts of the world.
The numbering system consists of both letters and numbers, depending on whether the dentist is referencing primary teeth (baby teeth that are lost as a person grows,) or permanent teeth.
Primary teeth are labeled on a human teeth diagram with capital letters A through T. There are a total of 20 primary teeth. The first tooth, tooth A, is the patient’s upper right molar, farthest to the back. The labeling then continues around to the front of the mouth to the other side, ending with tooth J on the left. The labeling then resumes with tooth K, the bottom left molar, farthest in the back, continuing around the front of the mouth to the right side again, where it ends with tooth T.
The adult permanent human teeth diagram looks different than the primary one because adults have 32 teeth, which means the teeth numbers for adults are 1 through 32.
Similar to the starting and stopping point of primary teeth labeling, tooth 1 in an adult mouth is the upper right third molar, the wisdom tooth. Counting continues around the front of the mouth the wisdom tooth on the top left, which is number 16. The labeling drops down to the bottom left wisdom tooth, tooth 17, and continues around the front of the mouth, ending with the bottom right wisdom tooth, which is labeled (can you guess?), number 32.
When looking at a human teeth diagram, it’s important to remember perspective. The diagram is set up to view the teeth from the perspective of the dentist. What is seen on the left side of the diagram is actually the right side of the patient’s mouth. The teeth numbers start on the patient’s right. If you are making an attempt to better communicate with your dentist about your teeth, you don’t want to send him searching for a problem in tooth 4 when you actually mean tooth 13.
Learning and knowing the labeling system for teeth can be a helpful way to communicate better with your dentist.