Your teeth are kept alive by a nerve or the pulp which lives inside the root of your tooth. The root of your tooth is covered by bone and gum tissue. The nerve in your tooth can die or become infected. This can be caused by a crack in the tooth, deep cavities/deep fillings or trauma/accidents and may cause swelling and infection. You may not even be aware that the tooth is dead or infected, but your dentist may notice changes in the colour of your tooth, changes in your gums (fistula) or changes in your x-rays. A root canal allows you to KEEP your tooth. After it has been determined that a root canal is necessary and possible, you are given freezing. The rubber dam is placed to keep your tooth free from germs and saliva and also to protect you. A small opening is made through the top of your tooth to access the nerve. Tiny files are used to remove the dead or dying nerve. The canal where the nerve lived is cleaned and shaped with hand and rotary instruments and is disinfected with an irrigant. The canal is then sealed with a rubber-like material, called gutta-percha to prevent re-infection.
Two appointments may be required to complete the root canal. If the dentist is unable to complete the root canal because it is too complicated an appointment with a specialist is necessary. A permanent filling is placed, likely at a later appointment, and then the tooth is ideally crowned in order to protect your investment. (Canadian Dental Association Information System).