A retreatment of the canal or orthograde preparation aims to completely remove the existing filling material, reach areas that were left untreated during a previous procedure, and thus ensure complete disinfection of the root portion. With the NiTi Endo ReStart file system, this task can be effectively but controlled in a few steps. The Endo ReStart Opener has a constant taper of 10%, a diameter of 030 mm, a length of 15 mm, a short active part (5 mm), a tip with 4 surfaces, is sterile, and reusable.