When a tooth gets infected due to a deep cavity or a crack, Root Canal Therapy can save the tooth. Root Canal Therapy involves removing the nerves and blood supply of the tooth, and the pulp from the canals in the roots of the tooth.
An abscess at the tip of the root can develop if left untreated. The abscess; which is an infection, can cause pain and swelling. If the infection has not been treated, the tooth may have to be extracted.