Why do kids have to lose their teeth?

Dear Dr. Cory:

Why do kids have to lose their teeth?

Lara Brown Greenville, North Carolina

Dear Lara:

Your first set of teeth, often called baby teeth, are designed to be used only for the first few years of life. They are not large enough or strong enough to be useful to you as an adult. But those baby teeth are still very important. They guide the second set of teeth, called permanent teeth, into their proper position.

Babies are born with both sets of teeth already growing in their jaws (twenty baby teeth and thirty-two permanent teeth). The baby teeth start to push through the gums at about six months of age and are all out at about age two. Between the ages of six through twelve, the baby teeth will be pushed out by the permanent teeth. The new teeth that grow in are larger and stronger, and are much more useful to a child about to become an adult.