blank chart for teeth names and numbers

Which Tooth is Which?

Trying to understand what a dentist says can be a dizzying experience. Dentistry has its own vocabulary. Learning this vocabulary, including teeth names, can help you communicate with your dentist better. When you understand what your dental team is saying, you feel more confident as a patient. Knowing your teeth names helps you understand your diagnosis and treatment.

Dentists assign numbers to your mouth for various reasons. Some numbers signify area, while others signify the condition of your oral health.

Parts of the Mouth

Dentists divide the mouth into four areas, or quadrants.

1. Quadrant 1 — top right
2. Quadrant 2 — top left
3. Quadrant 3 — bottom left
4. Quadrant 4 — bottom right


Notice that while the numbers go right to left on top and left to right on the bottom. It’s helpful to think of the numbers as they are on a clock. From the dentist’s perspective, quadrant 1 is on the top left. As you go clockwise around your mouth, the numbers get higher.

Gaps in the Gums

Unlike quadrant numbers, gum numbering is not for dividing parts of the mouth. The number assigned to the gums describes how deep the gaps are between your teeth and your gums. These numbers are described in millimeters. So the lower the number, the smaller the gap. It is preferable to have smaller gaps between your teeth and your gums. Larger gaps are signs of gum disease, plaque, and tartar buildup.

Dr. Kao specializes in the prevention, diagnosis, and treatment of periodontal disease, and the precise placement of dental implants. Contact Dr. Kao today for a checkup.

If you hear your dentist say a number between one and three, your gums are healthy. You have been brushing, flossing, and using antibacterial mouthwash on a regular basis. If you have a 4, your dentist may warn you about your risk for periodontal disease and bone loss. They will check to see if your gums bleed easily.

If your number is five or higher, a deep cleaning is necessary. This is to remove buildup between the teeth and gums.

Teeth Names & Numbering

Dentists have to identify, communicate, and record information about individual teeth. Globally, there are several systems to do this. In the United States, dentists use the Universal tooth numbering system. This system is accepted and approved by the American Dental Association (ADA). It is both clinical and radiographical. Clinical dentistry is “the study and treatment of conditions within the oral cavity. Radiographs are the x-rays dentists use in their clinical practice.

In the Universal numbering system, primary and permanent teeth are named differently. It has one drawback: there are no names for supernumerary (extra) teeth. The major advantage is it follows a sequential pattern is easy to understand.

Permanent Teeth

The image above is of the Universal numbering system for permanent (adult) teeth. The notation is simple. Teeth number from 1-32 sequentially starting in quadrant 1 and ending with quadrant 4.

Primary Teeth

The numbering of primary (baby) teeth begins with the upper arch, A-J, and includes both quadrants. The lower arch is named in a similar way, in reverse alphabetical order from T-K. Only capital letters from A-T are used in naming the primary teeth.


Lasting Dental Care

Dr. Kao is a dental specialist in Periodontics and Dental Implants in Los Angeles. He restores dental health and function with exceptional care and compassion. Dr. Kao’s practice in Downtown Los Angeles accommodates patients with diverse individual needs. Contact Dr. Kao for a dental appointment today!