From Primary to Molars: Types of Teeth

Your mouth plays a vital role in a variety of processes. It breaks food into small particles so it can be swallowed and digested. It enables verbal communication. And it serves as a first line of defense for your body by preventing microbes and other harmful agents from entering your system. Learning a little about the structure of your mouth will help you maintain the best possible oral health.

Your first teeth—called primary, deciduous, temporary, or baby teeth—form in the gums before birth and begin erupting at about 6 months of age. The complete set of 20 temporary teeth is usually in place by age 2 or 3. These teeth serve several important functions. They allow an infant to begin eating solid foods and to develop speech. They also act as placeholders, enabling the permanent teeth to align correctly as they grow in.

Beginning at about age 6 and continuing until age 12 or 13, the baby teeth fall out and are replaced by their permanent counterparts, plus an additional eight teeth. As many as four more teeth, often called the wisdom teeth, usually emerge between ages 17 and 21, completing the adult set of 32 teeth.

You have several different types of teeth, including incisors, canines, bicuspids, and molars. The variety in tooth shapes reflects the range of foods in the human diet.

Incisors: Eight teeth in the middle front of the jaw (four upper and four lower) that have straight, sharp edges shaped for cutting food.

Canines: Four larger teeth, also called cuspids or eyeteeth, with sharp points designed for ripping or tearing

Bicuspids and molars: The remaining teeth—eight bicuspids (sometimes called premolars) and eight to 12 molars, which have broad, flat surfaces with small mounds for grinding food

Source: Dental Health for Adults: A Guide to Protecting Your Teeth and Gums. Copyright © by Harvard University. All rights reserved.