If a tooth is knocked completely out, immediate action is crucial. The tooth should not be outside the mouth for more than one hour. Gently rinse the tooth with water, but do not scrub or use soap or other cleaning agents. If possible, try to place the tooth back into its socket. Keeping the tooth moist is essential for saving it. If re-insertion isn't possible, store the tooth in milk or a glass of water (with a pinch of salt) to help preserve it. The treatment options will depend on how long the tooth has been out and how it's been stored. Dr. Baker may begin root canal treatment depending on the tooth's stage of root development. Be sure to contact your dentist immediately for further care.