Accidents happen! Teeth can get knocked out or pushed into the gingiva. When this occurs, the nerve connected to the tooth becomes severed. The tooth may need a root canal, as well as splinting to retain the tooth in the site of injury.
If the tooth remains untreated, it may become necrotic and an infection can form. Signs of this may involve pain, swelling, exudate, bleeding, gingival fistula, unusual taste, and darkening of the tooth.
(not all symptoms are always present)