If you were trying to tell your dentist which tooth was giving you problems, chances are you'd say something like, "It's the pointy one on the top left side of my mouth," or "It's the fifth one back from the front on the right side on the bottom." With 32 teeth in the typical adult's mouth, the descriptions can get pretty complicated and confusing.

Numbering systems have been developed to have a standard way of referring to particular teeth. Two are commonly in use today. The Universal Numbering System has been adopted by the American Dental Association (ADA). Most general dentists use this system. The Palmer Notation Method is used by many orthodontists and oral surgeons.

In the Universal Numbering System, the teeth that should be there are numbered. If you are missing your wisdom teeth (the molars farthest back in your mouth), your first number will be 2 instead of 1, acknowledging the missing tooth. If you've had teeth removed or teeth are missing, the missing teeth will be numbered as well.

Illustrations created by Simple Steps designer Michael Becker

Universal Numbering System Adults In this system: Tooth number 1 is the tooth farthest back on the right side of your mouth in the upper (maxillary) jaw. Numbering continues along your upper teeth toward the front and across to the tooth farthest back on the top left side (which is number 16). The numbers continue by dropping down to the lower (mandibular) jaw. Number 17 is the tooth farthest back on the left side of your mouth on the bottom. Numbering continues again toward the front and across to the tooth farthest back on the bottom right side of your mouth (which is number 32). Children In the original system, children's 20 primary teeth are numbered in the same order, except that a small letter "d" follows each number. This letter indicates that it is a deciduous (primary or "baby") tooth. So, a child's first tooth on the upper right would be 1d and the last tooth on the lower right would be 20d. However, most dentists and insurance companies now use a modified version of the Universal Numbering System for children. This version uses the letters A through T instead of the numbers 1 through 20. So, a child's first tooth on the upper right would be A. The last tooth on the lower right would be T. Palmer Notation Method Adults In this system, the mouth is divided into four sections called quadrants. The numbers 1 through 8 and a unique symbol are used to identify the teeth in each quadrant. The numbering runs from the center of the mouth to the back. In the upper right section of the mouth, for example, tooth number 1 is the incisor (flat, front tooth) just to the right of the center of the mouth. The numbers continue to the right and back to tooth number 8, which is the wisdom tooth (third molar.) The numbers sit inside an L-shaped symbol used to identify the quadrant. The quadrants may also be identified by letters. For example, "UR" or "URQ" would mean the upper right quadrant. Children In children, the Palmer Notation System uses uppercase letters instead of numbers. Following the same order as for adult's teeth, children's 20 primary teeth are lettered "A" through "E" in each quadrant. The same symbol is used to identify the quadrants.