It is a branch of dentistry that deals with the treatment of root canals in teeth. Under the enamel and dentin layers of the tooth, there is a section called "pulp" where the vessels and nerves that provide the vitality of the tooth are located. This section, called the "pulp chamber" in the crown of the tooth, extends to the end of the tooth roots. In case the pulp is inflamed for any reason, the nerve of the tooth should be removed, the canals should be sterilized and then filled. Root canal treatment is applied in one session for living teeth, and generally in two sessions for teeth that have lost their vitality.