old think: When a young child loses a tooth, wash it off and wrap it in gauze until you can get prompt medical attention.
new think: Place the errant tooth in a container of cold milk and get to the dentist or emergency room immediately.
why: If her tooth is shattered, or if it's a baby tooth, doctors or dentists won't bother to reattach it. But if there's a big piece of a permanent tooth intact, save it. Doctors will be able to reimplant the tooth and bond around it to make it look normal. While it's fine to gently rinse any dirt off, don't wash the tooth thoroughly or you could lose the roots. Ideally, stick the tooth right back in its socket until you get medical attention; saliva is good for the tooth and keeps the roots from dying. To stop her gums from bleeding, it's best to roll up a piece of gauze and have her bite down on it.