Ultrasonic insert kit for non-surgical reinterventions in endodontic treatments, consisting of: Endodontics. Retreatment. Micro-ultrasonic inserts for atraumatic extractions and releases. Removal of posts, extraction of cones, and release of instrument remnants. Contents: 5 inserts: ET18D, ET20, ET25, ETBD, and ETPR, 1 sterilizable key, and 1 stainless steel box/support.