A child will usually have 20 teeth by age 2. A child will usually lose it's first tooth when it is about 7. George Washington did not have teeth made out of wood, but he did have teeth made out if hippopotamus teeth. He also had teeth made out of ivory, lead, human teeth, and cow and sheep's teeth. The hardest thing in your body is the enamel on your teeth.
Mammals have two types of teeth, the primary teeth and the permanent teeth.
Your teeth started forming before you were born. The bristles of toothbrushes were originally made from the hair of hogs and cows. The real name for baby teeth is milk teeth. A Chinese dentist once built a tower out of 28,000 human teeth . Sharks have at least 40 sets of teeth in their life time.