Teeth are made up of different layers — enamel, dentin, pulp, and cementum. Enamel, which is the hardest substance in the body, is on the outside of the tooth. The second layer is dentin, which is softer than enamel, and the deepest layer inside the tooth is pulp, which consists of nerves and blood vessels. Cementum is on the root of the tooth and is beneath the gums.
The number and types of teeth a person has changes as they age. Typically, people have two sets of teeth during their life — primary, or baby teeth, and permanent, or adult teeth. In this article, we look at the teeth that children and adults have, as well as their functions.
Humans have the following types of teeth:
Incisors
Incisors are the sharp teeth at the front of the mouth that bite into food and cut it into smaller pieces. They are flat with a thin edge. They are also called anterior teeth.
Both children and adults have eight incisors — four central incisors at the front of the mouth, two on each row, with one lateral incisor positioned on either side of them.
Canines
Canines are the sharp, pointed teeth that sit next to the incisors and look like fangs. Dentists also call them cuspids or eyeteeth. Canines are the longest of all the teeth, and people use them to tear food.
Both children and adults have four canines. Children usually get their first permanent canines between the ages of 9 and 12. The lower canines tend to come through slightly before those in the upper jaw.
