Endodontics is a specialty of dentistry, which deals with the tooth pulp. The pulp (containing nerves, arterioles and venules as well as lymphatic tissue and fibrous tissue) can become diseased or injured and thus is unable to repair itself. The pulp then dies and endodontic treatment is required. The word comes from the Greek words endo meaning inside and odons meaning tooth. Literally taken, it means study of that which is "inside the tooth”.

Root Canal Treatment:

The most common procedure done in endodontics is root-canal therapy, which involves the removal of diseased pulp tissue. The tooth consists of two parts: the crown and the root. Inside each root is a channel that runs the length of the tooth. This channel, called ‘the root canal’, contains the pulp (nerves, blood vessels and soft tissues). The tooth aches when the gum is inflamed or infected. In order to save such tooth, root canal treatment is performed which involves the removal of the inflamed root canal contents, which are replaced with an inert, proven, biocompatible material. This tooth is then brought back to form and function by fixing a crown on it.

Periapical Lesion:

Most periapical diseases are induced as a result of direct or indirect involvement of oral bacteria. The etiologic factors are oral contaminants through the root canal or degenerating pulpal tissues. Therefore, mere surgical removal of the periapical lesions without proper root canal disinfection and obturation will not result in the healing of periapical tissues.

Conventional root canal treatment is aimed primarily at eliminating these bacteria as completely as possible. Treatment options to manage large periapical lesions range from non-surgical root canal treatment and /or apical surgery to extraction.  Current philosophy in the treatment of teeth with large periapical lesions includes non-surgical root canal treatment. When this treatment is not successful in resolving the periradicular pathosis, additional treatment in the form of surgical intervention (curettage and apical resection with retrograde filling) is given.