A root canal, or endodontic treatment as it is also known, is necessary to save a tooth from extraction when the pulp becomes infected or exposed. Deep inside the tooth is the pulp, which contains blood vessels, nerves, and connective tissue. The pulp can become inflamed or infected for a variety of reasons, including deep decay extending into the pulp, repeated dental procedures on a particular tooth, or fracture or breakage. 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 severe pain or lead to a dental abscess.