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Procedures

Endodontic treatment

Procedure overview

Learn about the dental procedure, when it is generally prescribed, and other information which can increase your knowledge of the topic.

Alternate terms: Root canals.

Root canal therapy, ("endodontic treatment") is a procedure in which access to the hollow interior of the tooth (the "pulp) is made, in order to remove inflamed, infected or necrotic (dead) nerve and blood vessel tissue. The root canals are disinfected, enlarged and hermetically sealed to the root tips with a rubbery filling material. Finally, the access hole into the tooth is filled with any of the available filling materials like silver amalgam, composite resin, porcelain or gold (often at a separate appointment). Your dentist may recommend that the tooth be crowned following endodontic treatment, especially if it has multiple cusps or multiple roots, and is structurally compromised. Normally the front six teeth in both jaws only have single roots, and many times those teeth don't need to be crowned after endodontic treatment.

X-ray of tooth abscess (infection) that resorbed bone around an incisor root apex

Figure 1: An abscess occurred in this patient's tooth #23 (probably in response to a wrestling injury which he recalled having sustained years earlier). The dark area at the root tip (see arrow) shows where the inflammation and infectious fluid had dissolved away some of the bone. The patient's first symptom was the development of a numb lower lip on his left side. This was due to the infectious fluid accumulating in the mental nerve canal, which applied pressure to the nerve. He had no pain, but the tooth was notably darker than its neighboring teeth. Getting to the infected root tip was accomplished most easily through the tooth, by way of the root canal (visible as the dark stripe running down the middle of tooth #23).

Endodontic treatment is prescribed for teeth that have been diagnosed with an abscess, irreversible pulpitis, chronic apical periodontitis, or are necrotic ("dead"). Endodontic treatment is also prescribed if the clinical crown of the tooth (the part that is visible protruding through the gum tissues) is badly broken down and would require structural posts to be placed in order to restore the tooth.
Learn more: Diagnoses › Acute apical abscess
Learn more: Diagnoses › Chronic apical periodontitis
Learn more: Diagnoses › Irreversible pulpitis
Learn more: Diagnoses › Necrotic teeth
Learn more: Diagnoses › Phoenix abscess

Sometimes a tooth that requires endodontic treatment will be obvious just from the X-ray (Figure 1), if there are obvious changes in the bone near the root tip(s), even in the absence of symptoms. Sometimes teeth with deep decay require root canal treatment even though they may not hurt or be sensitive. A tooth that is particularly sensitive to hot temperatures, but is relieved by cold likely has gas from bacteria inside of it (i.e. an infection). Heating the tooth heats the gas, which, constrained by the hard shell of the tooth around it, cannot expand.

The result is that the pressure in the tooth increases and puts pressure on the nerve that you feel as pain. Teeth with such symptoms typically require root canal therapy to eliminate the infection. Teeth that produce continuous dull, achy pain frequently require root canal treatment. Teeth that have a prolonged, aggravated pain response to cold may need root canal treatment.

Draining sinus tract from combination periodontal-endodontic abscess

Figure 2: This problem was evident to the patient—a draining "sinus tract" which had found its way from the tooth root, through the thin overlying bone, and through the patient's gums. The first symptom was a bad taste in her mouth. This tooth had a history of "avulsion" (it was knocked out completely) when the patient tripped and fell on a slippery sidewalk. The tooth abscess occurred five years after the accident, and required endodontic therapy (this tooth's root canal treatment is described under "The process").

If you have been taking bisphosphonate medications, you may not be a candidate for tooth removal without suspending the medication for a period of time prior to the extraction. Ask your dentist whether endodontic treatment of the tooth may be an option if the tooth requires immediate treatment.