Root canal or endodontic treatment—treatment done to the inside of the tooth—is necessary when the pulp becomes inflamed or infected. The inflammation or infection can have a variety of causes: deep decay, repeated dental procedures on the tooth, faulty crowns, or a crack or chip in the tooth. In addition, trauma to a tooth may cause pulp damage even if the tooth has no visible chips or cracks. If pulp inflammation or infection is left untreated, it can cause pain or lead to an abscess (swelling with pus).
During root canal or endodontic treatment, the inflamed or infected pulp is removed and the inside of the tooth is carefully cleaned and disinfected, then filled and sealed with a rubber-like material called gutta-percha. Afterwards, the tooth is restored with a crown or filling for protection. After restoration, the tooth continues to function like any other tooth.