Procedure, which is indicated in case of failure of the initial endodontic treatment.
Its essence lies in detailed and complete removal of the old root canal filling, healing the inflamation by complete desinfection of root canals system and making new 3D obturating root canal filling.
Most common reason of first root canal system treatment failure is not efective desinfection of root canals system and insuficient hermetical seal of obturating filling.
Another reasons should be dificult anatomy of root canal system so there can remain some canals without apropriate treatment or separation of root canal instrument.
Incorrectly endodontictly treated teeth are ideal place for reproduction of bacterias. Cyst or chronic inflamation forms in the root apex area and so bacterieas can easily spread to the whole body.