Avulsion is when a tooth is completely knocked out of its socket. Common causes are collisions, falls, road accidents, protruding front teeth, and sports. If a tooth is avulsed, stay calm, handle the tooth by the crown only and rinse it in water. Try placing it back in the socket and biting down. Otherwise, store it in milk and go to the dentist immediately. The dentist will evaluate if replanting is possible and may perform a root canal. Correcting malocclusion or wearing protective gear for sports can prevent such injuries.