How is a root canal procedure done?

After adequate anesthesia, the main nerve in the center of the tooth is accessed by making a hole in the top of the tooth. Instruments ( files) are used to remove the remains of the nerve and blood vessels and to shape the inside of the root so that it can be sealed so that no further bacteria can enter the tooth.

A root canal is a filling of the root part of the tooth. The procedure is similar to having a tooth filled. First, the tooth is numbed and a rubber shield called a rubber dam is placed over the tooth. This rubber dam keeps the area sterile and will protect you from the small instruments that will be used to remove the infected part of the tooth. Once the infected part of the tooth is removed (the pulp), the canal is shaped, and the root is filled with a filling.

Root canal therapy is a complex procedure that requires both skill and experience. The dentist numbs the area of the infected tooth with local anesthesia. A clamp is placed over the tooth, and a rubber membrane (rubber dam) is spread over the clamp to isolate the tooth and prepare it for the procedure. A small hole is made through the tooth, and into the pulp. The pulp is then removed with small stainless steel files of increasing diameter. After the pulp has been removed, the inside walls of the roots are shaped, almost like a sculpture. Nickel/Titanium files that fit on a slow speed drill can aid in shaping the canals. During the procedure, fluids (irrigants) such as sodium hypochloride (bleach) a compound containing ethylenediamine-tetraacetate (EDTA), and/or chlorhexidine are used to both kill remaining pulp tissue and bacteria within the roots, and remove dentin shavings produced by the files.

After the pulp is removed and the inside of the roots shaped, the canal is dried with paper cones. The canal(s) are then filled with Gutta-percha. Gutta-percha is a miraculous substance that was first introduced by Bowman in 1867. It is a purified form of Mazer Wood Trees indigenous to Indonesia and Malaysia that is combined with zinc oxide and other materials to form the rubbery filling that is placed into the tooth roots. The Gutta-percha is then cemented into the roots with a sealer that usually contains zinc oxide and eugenol. The goal of the filling procedure is to hermetically seal off the tooth against bacteria.

After it is determined that root canal treatment is needed, then the process is divided into four stages usually completed in two or more appointments. The stages are 1. accessing, measuring and disinfecting the root canal space, 2. shaping and enlarging the space, 3. filing the space with a sterile, bio-compatible material and, 4. restoring the broken down tooth to proper contour and function.

During the accessing, measuring and disinfection stage, the tooth would customarily be isolated by means of a rubber dam which is temporarily affixed around the offending tooth. Then x-rays to measure the tooth and finally the canal debris is carefully removed, the walls scrubbed and disinfected, preparing the tooth for the next stage.

Shaping and enlarging the root canal space is done with the rubber dam in place as is the filling stage. This shaping procedure facilitates the placing of the final filling as well as further cleansing the space. Special instruments are used by hand and with the dental hand piece (drill) to accomplish this step.

The third stage, filling the space is again accomplished with rubber dam, perhaps at the same visit as stages one and two. There are many filling materials available but all of them are inert, sterile and dense. Obliterating any voids where bacteria might linger and grow.

The fourth and final stage, restoring the tooth usually is done on a subsequent visit or visits. For many reasons this most important step must be accomplished punctually and carefully. The final restoration of the tooth would normally be a crown or a bridge and this stage is often neglected resulting many times in complete failure of the entire root canal procedure.
A root canal procedure often involves from one to three visits. During treatment, your general dentist or endodontist (a dentist who specializes in problems of the pulp) removes the diseased pulp (the soft tissue of a tooth that contains nerves, blood vessels and connective tissue). The pulp chamber and root canal(s) of the tooth are then cleaned and sealed.

Here's how your tooth is saved through treatment:
  1. First, an opening is made through the crown of the tooth into the pulp chamber.
  2. The pulp is then removed. The root canal(s) is cleaned and shaped to a form that can be filled.
  3. Medications may be put in the pulp chamber and root canal(s) to help get rid of germs and prevent infection.
  4. A temporary filling will be placed in the crown opening to protect the tooth between dental visits. Your dentist may leave the tooth open for a few days to drain. You might also be given medicine to help control infection that may have spread beyond the tooth.
  5. The pulp chamber and root canals are filled and sealed.
  6. The temporary filling is removed and the pulp chamber and root canal(s) are cleaned and filled.
  7. In the final step, a gold or porcelain crown is usually placed over the tooth. If an endodontist performs the treatment, he or she will recommend that you return to your family dentist for this final step.

Continue Learning about Root Canal Therapy

What are the signs that a root canal is needed?
Dr. Saul N. Miller, DDSDr. Saul N. Miller, DDS
At times there may be no signs that you notice. This is why it is best to have regular check-ups to ...
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How do I know if I need a root canal?
Stanislav MolineStanislav Moline
(You probably meant root canal treatment because root canal is a space within a tooth) The answer...
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Should I talk to my dentist if I still feel tooth pain after a root canal?
Gary L. Sandler, DDSGary L. Sandler, DDS
Hopefully your dentist has explained to you what to expect after you have received an interim or fin...
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What may happen before a root canal treatment?
William M. Litaker Jr., DDSWilliam M. Litaker Jr., DDS
Before root canal treatment an x-ray will be taken of your tooth. Your tooth will also be numbed wit...
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.