If a tooth is completely knocked out of your mouth. Time is vital, and is important that you are treated promptly. The tooth should be handle very carefully, avoiding touching the root surface itself. If it is possible, the tooth should be placed back into the socket in the mouth as soon as possible. The less time the tooth is out of its socket, the better the chance of saving it. You can also keep the tooth moist by keeping it in milk.
Once the tooth has been placed back in the socket, your dentist or endodontist will evaluate it and check for any other dental injuries. A stabilizing splint will be placed for a few weeks. The endodontic treatment will be started within a couple of weeks after the replantation, except in cases of a tooth in a very young child.
The length of time the tooth was out of the mouth, its management, and storage before getting professional help will influence on the chances of saving the tooth.