A tale of two sets of teeth
Most people have two sets of teeth during their life: a set of primary or “baby” teeth and the permanent or "adult" teeth.
Besides helping children chew and pronounce words, the primary teeth hold a place in the jaws for the permanent teeth, which begin to push through the gums, or "erupt," as the primary teeth are shed.
While most children have 20 primary teeth—10 in each of the upper and lower jaws—these teeth eventually are replaced by 32 permanent teeth, 16 in each jaw.
The first permanent molars usually erupt between ages 6 and 7 years. For that reason, they often are called the "six-year molars." They are among the "extra" permanent teeth in that they don’t replace an existing primary tooth. These important teeth sometimes are mistaken for primary teeth. However, they are permanent and must be cared for properly if they are to last throughout the child’s lifetime. The six-year molars also help determine the shape of the lower face and affect the position and health of other permanent teeth.
The last of the permanent teeth to appear are called "third molars," or “wisdom teeth.” They usually begin to erupt between ages 17 and 21 years. Because they are so far back in the mouth, third molars often are not needed for chewing and are difficult to keep clean. Your dentist may recommend their removal to prevent potential complications when third molars are erupted partially or are impacted.
Please contact the ADA if you have questions about this article.
©2010 American Dental Association. All rights reserved. Reproduction or republication is strictly prohibited without the prior written permission from the American Dental Association.