If the tooth is a permanent tooth, time is extremely crucial. Immediately stick the tooth back in the socket. Don't worry about getting it in straight or having it turned backwards, just get it in the socket and immediately call your dentist. If you are uncomfortable placing the tooth in the socket, put it in a glass of milk and get your child to the dentist as quickly as possible. If the tooth is a baby tooth, do not put it in the socket because damage to the permanent tooth can occur. When in doubt, put the tooth in milk and see your dentist immediately.