Endodontics is the field of dentistry dealing with the tooth pulp, tooth root, and associated structures and pathologies. The primary procedure involved in endodontics is root canal therapy. General dentists are trained in endodontic procedures, but mostly stick to the straight forward root canals, usually in the anterior teeth. The more complex cases are usually referred to an Endodontist.
Endodontists complete an additional 2 to 3 years of residency training before earning a Masters degree in endodontics. These specialists deal with the complicated cases which general dentists are not experienced enough and/or comfortable enough to treat. These include teeth with especially narrow canals, obstructed canals, extensive branching of canals, and teeth with extremely curved roots known as dilacerations. In addition to the more extensive training and experience in the various endodontic treatments, most endodontists have special technology that general dentists do not have, like endodontic microscopes.
In addition to root canal therapy, other endodontic procedures include draining infections in and around tooth roots, periradicular surgery known as apicoectomies, stabilizing root fractures, and internal bleaching.
The most common endodontic procedure is root canal therapy, which is often referred to as endodontic therapy or simply as a root canal. A root canal is usually performed when a patient has an infection that has reached the dental pulp of a tooth. Infections in the dental pulp will cause inflammation that can cause extreme pain because the pressure is contained with in a bony structure, so there is no outlet. In some cases, the nerve will die and so the patient will not have the normal excruciating pain from this infection, but it still needs to be treated because the infection can spread to form an abscess at the apex of the tooths root. If the infection goes untreated long enough, it can spread along the fascial spaces to cause massive swelling of the face and can potentially spread to the mediastinum or to the brain. This type of infection can not be cleared by your immune system because the source of the infection is confined to an area with limited access inside the tooth. Antibiotics may help treat associated abscesses, but will not clear an endodontic infection because the limited blood flow into a tooth is not enough to provide sufficient levels of the drugs to the infected area.
To eliminate the infection and prevent further spreading, a root canal must be performed. Access to the pulp chamber is created by drilling into the tooth from the lingual (tongue side) for anterior teeth, or from the occlusal (chewing surface) for posterior teeth. Once the chamber is adequately opened, the canals that contain the nerve, blood vessels and the infection must be cleaned out with small files. The canals are carefully instrumented with files that sequentially increase in size and can be done either manually or via rotary drill. Radiographs are taken throughout the procedure to ensure that the canals are reaching all the way down to the tip of the root so that no remaining infected canal area is left following the procedure. Sodium hypochlorite or another irrigant is periodically injected to rinse out the canals of any debris. Following the cleaning procedure, the canals are dried and filled with a substance known as gutta percha. To finish the procedure the teeth are restored usually with a post, core and crown, although anterior teeth can often be restored with a simple filling placed over the opening. If done correctly, any infection at the tip of the roots will resolve on their own. However, large abscess may need to be incisionally drained and may also require antibiotics.
Placement of gutta percha during a root canal procedure
Endodontic residency is among the most competitive dental specialty programs. In 2006, 240 applicants applied to the 12 endo residency programs that participated in the Postdoctoral Application Support Service (note that there are many more residency programs that do not participate in PASS). Depending on the program, endodontic residency lasts between 2 and 3 years. According to the ADEA, there are over 4,000 endodontists in the United States as of 2006. To find a list of accredited endodontic residency programs in the United States, visit The American Association of Endodontists website.