Can people have two sets of teeth at the same time?

Humans normally have two sets of teeth during their lifetime: primary teeth (also known as baby teeth) and permanent teeth.

- Primary teeth: There are 20 primary teeth. They start to erupt (come in) at around 6 months of age and are usually all in place by age 3. As your child's jaw grows, their permanent teeth eventually push out the primary teeth to make way for them.

- Permanent teeth: When you are about 6 or 7, your body starts replacing your primary (baby) teeth with permanent ones. By adulthood, most people have a total of 32 permanent teeth: 16 on the upper jaw (maxilla) and 16 on the lower jaw (mandible).