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A root canal is a treatment used to repair and save a tooth that is badly decayed or infected. A tooth's nerve and pulp can become irritated, inflamed, and infected due to deep decay; repeated dental procedures on a tooth; or large fillings, a crack, or chip in the tooth. It also can happen because of trauma to the face.
During a root canal procedure, the nerve and pulp of the tooth are removed and the inside is cleaned and sealed. Without treatment, the tissue surrounding thetooth will become infected and an abscess may form.
A tooth's nerve is not vitally important to a tooth's health and function after the tooth has come through the gums. Its only function is sensory -- to give the sensation of hot or cold. The absence of a nerve won’t affect how your tooth works.
Root canal procedures have the reputation of being painful. But the procedure itself is no more painful than having a filling placed.
