Root canal therapy

Definition

Root canal therapy, also known as endodontic treatment, is a dental procedure in which the diseased or damaged pulp (nerve) of a tooth is removed and the inside

areas of the nerve chambers or root canals are filled and sealed.

Purpose

Root canal therapy has become a common dental procedure. More than 14 million are performed each year, with a success rate of 95%, according to the American Association of Endodontists. Inflamed or infected pulp (pulpitis), often causing a toothache, is removed to relieve the pain and prevent further complications for the patient.

Precautions

Once root canal therapy is finished and the nerve is removed, the tooth becomes brittle over time and can fracture and break easily. Therefore the tooth requires extra protection and will need a crown.

Description

Root canal therapy may be performed by a general dentist or by an endodontist, a dentist who specializes in endodontic procedures. The pulp of the tooth consists of soft tissue containing the blood supply from which the tooth gets its nutrients and by which the tooth senses hot and cold. This tissue is vulnerable to damage from deep dental decay, accidental injury, tooth fracture, or trauma from repeated dental procedures (such as multiple fillings over time). Infection may produce pain that is severe, constant, or throbbing, as well as prolonged sensitivity to heat or cold. Swelling in and around the surrounding gums along with facial swelling may be seen. However, in some cases, the pulp may die so gradually that there is little noticeable pain or swelling.

Root canal therapy is performed under local anesthesia . A thin sheet of rubber, called a rubber dam, is placed in the mouth to isolate the tooth. The endodontist makes an opening through the natural crown of the tooth into the pulp chamber. He will then determine the length of the root canal, usually with a series of x rays. Small wire-like files, called broaches, are used to clean the entire canal space of diseased pulp tissue and bacteria . The debris is flushed out (irrigated) with sterile water. The canals are also slightly enlarged and shaped to receive an inert (non-reactive) filling material called

KEY TERMS

Abscess —Gum tissue filled with pus as the result of infection. This swelling exerts pressure on the surrounding tissues, causing pain.

Apicoectomy —Also called root resectioning. The root tip of a tooth is accessed in the bone and a small amount is taken off away. A small filling is placed to reseal the canal.

Crown —The natural crown of a tooth is that part of the tooth covered by enamel. Also, a restorative crown is a protective shell that fits over a tooth.

Endodontic —Pertaining to the inside structures of the tooth, including the dental pulp and tooth root, and the periapical tissue surrounding the root.

Endodontist —A dentist who specializes in the diagnosis and treatment of disorders affecting the inside structures of the tooth.

Extraction —The surgical removal of a tooth from its socket in the bone.

Gutta-percha —An inert latex-like substance used for filling root canals.

Pulp —The soft innermost layer of a tooth, containing blood vessels and nerves.

Pulp chamber —The area within the natural crown of the tooth occupied by dental pulp.

Pulpitis —Inflammation of the pulp of a tooth involving the blood vessels and nerves.

Root canal —The space within a tooth that runs from the pulp chamber to the tip of the root.

Root canal treatment —The process of removing diseased or damaged pulp from a tooth, then filling and sealing the pulp chamber and root canals.

gutta-percha. However, the tooth is not filled and permanently sealed until it is completely free of the active infection and/or bacteria. The endodontist will place a temporary seal, or leave the tooth open to drain, and prescribe an antibiotic to counter any spread of infection from the tooth. The patient may need a number of return visits to the dental office while the root canal is being treated, and the infection brought under control.

Preparation

There is no typical preparation for root canal therapy, as the treatment is done on an emergency basis due to sudden injury or pain. The reasons why root canals are thought to be so painful are due to the sudden injury and build-up of infection in the tooth. Normal doses of local anesthetic used by the dentist are not always effective against the degree of pain the patient is already feeling. Occasionally, even high amounts of anesthesia aren't effective until the infection can be drained and brought under control.

Aftercare

The tooth may be sore for several days after filling. Such pain relievers as ibuprofen (Advil, Motrin) may be taken to ease the soreness. Ibuprofen is an effective antiinflammatory drug and can help reduce the inflammation caused by the infection. The tissues surrounding the tooth may also be irritated due to the infection, but also due to the rubber dam used to isolate the tooth during the root canal treatment. Rinsing the mouth with warm salt-water rinses several times a day is helpful. The patient should avoid chewing on the treated tooth for several days. A follow-up appointment should be scheduled with the dentist for six months after treatment to make sure the tooth and surrounding structures are healthy.

Risks

There is the possibility that the root canal treatment will not be successful the first time. If infection and inflammation recur and an x ray indicates re-treatment is feasible, the old filling material is removed and the canals are thoroughly cleaned out. The dentist will try to identify and correct problems with the first root canal treatment before filling and sealing the tooth a second time.

In cases in which an x ray indicates that re-treatment cannot correct the problem, endodontic surgery may be performed. An apicoectomy, or root resectioning, is the procedure by which the root portion of the tooth is accessed through the gum tissue above or below the tooth in the bone. A small portion of the root tip is taken off and a small filling is placed to reseal the canal.

In some cases, root canal treatment, re-treatment, and apicoectomy surgery are not effective and the tooth must be extracted.

Results

With successful root canal treatment, the restored tooth can last a lifetime.

Resources

PERIODICALS

ADA Division of Communication. "Getting to the Root of Endodontic (Root Canal) Treatments." Journal of the American Dental Association (JADA) (March 2001).

ORGANIZATIONS

American Association of Endodontists. 211 East Chicago Avenue, Suite 1100, Chicago, IL 60611-2691. (800) 872-3636. <http://www.aae.org>.

American Dental Association. 211 East Chicago Avenue, Chicago, IL 60611. (312) 440-2500. <http://www.ada.org>.

OTHER

Dentistry on the Web. 497 Main Street, Ansonia, CT 06401. (203) 735-4701 <http://www.smilekeepers.com/Dental_Links/dental_links.htm>.

"Root Canal Therapy." Tooth Talk and Your Health with Dr. Frank Gober. Radio Talk Show, Fort Lauderdale, Florida. <http://www.toothtalk.com/>.

Root Canal—Saving Precious Teeth (television clip). ADA Dental Minutes, August 17, 2000.

Cindy F. Ovard, RDA