Most likely, the Tooth Fairy doesn’t actually do anything real with the teeth —it’s a folklore character, and the common child-friendly version is that she collects the tooth and leaves a small gift or money in return.

Quick Scoop

Different stories give different playful answers:

  • Some versions say the teeth are kept as magical keepsakes or part of a fairy collection.
  • Others joke that they’re used to make fairy dust, castles, or other magical things.
  • In real-world folklore, the tradition grew from older customs where children’s lost teeth were exchanged, buried, or tossed away for luck or protection.

The honest answer

There’s no verified real-life use for the teeth, because the Tooth Fairy is a legend rather than a documented real being. The fun of the story is the mystery: kids lose a tooth, and the Fairy leaves a surprise under the pillow.

If you want the kid-friendly version

You can say:

“She collects them, keeps them safe in fairy land, and leaves a little surprise for you.”

That keeps it magical without making it too complicated.

Bottom line

If you’re asking in the folklore sense, the Tooth Fairy is usually said to collect teeth and trade them for a reward ; if you’re asking literally, no one knows, because the Tooth Fairy is part of a story tradition.