Root canal treatment (also referred to as root canal therapy or endodontic therapy) is necessary when a cavity reaches all the way to the nerve of the tooth. Sometimes deep restorations or trauma to a tooth may cause the nerve to be damaged to the point it needs root canal therapy. Once the nerve is damaged it begins to die and the dead nerve must be removed. If the dying nerve is not removed an abscess can form which can be a dangerous and painful situation. Symptoms that the pulp has become infected may include sensitivity to hot/cold or sweets, pain, swelling, pain when biting and tooth discoloration. Sometimes, however, no symptoms are apparent and the person is unaware of any problem until a checkup.
A root canal is performed to clean out the infected tooth pulp, and disinfect the canals of the tooth. Once the infection is resolved, the canal(s) are filled to prevent any further infection. After a root canal, a tooth is restored with a filling or a crown.