Root canal therapy is a method of preventing tooth infection in a tooth whose structure has been damaged due to decay or trauma. This can occur when decay works its way around a filling or when a filling comes lose, when a tooth is cracked or broken due to trauma, or when unchecked tooth decay makes its way into the pulp, or fleshy core, of a tooth.

Sometimes it is obvious that root canal therapy is needed due to the appearance of symptoms. These include tooth sensitivity, pain in the tooth, pain with chewing, ear or eye pain, the breaking of a tooth, and pain or swelling in the jaw. It is possible that nothing indicates that there is a need for root canal therapy and that the New Brunswick dentist finds it upon examining the teeth during another procedure or during a regular dental cleaning.

The main goal of root canal therapy is to prevent the loss of a tooth. There is nothing that is as good in form or function as a natural tooth, and retaining as much of the natural teeth for as long as possible is one of the goals of dentistry.

With a root canal, diseased enamel (outer layer), dentin (inner layers), and pulp (fleshy core including nerves, blood vessels from the jaw, and connective tissue) are removed. The empty hollow of removed material is then smoothed so that it can be filled without leaving spots for bacteria to hide. The hollow is disinfected, the space is filled with a rubber like substance, and either topped with a temporary filling or left open to drain. Antibiotics may be administered to fight any possible infection that may have spread. On the next visit, the area is carefully examined for inflammation and healing, and a permanent crown is placed to protect the site from the forces of chewing.

It is possible for root canal therapy to fail. Many teeth have multiple roots, and there is a lot of variation between different people, so it is easy to miss multiple roots or other anatomic differences within the teeth. These areas can harbor infection and continuing decay, which can cause the tooth to continue to deteriorate and result in its ultimate failure and removal. Sometimes the shape of the removed material makes it difficult to fill the space without leaving a space or leaves material out of the line of sight of the dentist. Sometimes, there is simply a hole in the tooth that the dentist could not see, due to the previous decay. These problems result in failure of the root canal.

If the decay and infection are all removed successfully, and the blood supply to the tooth is still intact, the treated tooth will remain healthy, and the root canal will maintain the health of the tooth, the highest goal of dentistry.