Endodontic treatment, commonly referred to as canal treatment, is the treatment of a tooth whose pulp has been irreversibly damaged by caries or injury. The treatment procedure involves the removal of infected tissue, its decontamination and the filling of root canals. The treatment is under anesthesia and depending on the state of the tooth, it requires one or several visits. Reendo is an endodontic treatment of the tooth which has already undergone such treatment and for various reasons (most often due to the superinfection of the canal) requires a secend procedure. This treatment requires more work from the dentist and most often requires more visits. Every tooth after endodontic treatment requires reconstruction. Depending on the amount of tooth tissue loss, it is possible to use composite fillings or prosthetic restorations such as inlay, onlay, endocrown, crown.