Stepback течникуе, Following the preparation of the coronal part of the root canal, the apical preparation may also be carried out using the stepback technique. Starting with the size 15 file at the working length, and progressing to sizes 20 and 25, an apical stop is made.
Copious irrigation and recapitulation with fine files will prevent build-up of canal debris. The master apical file will usually be no greater than 25 or 30. The apical portion of the canal is now tapered by stepping back. A file one size larger than the master apical file is worked with balanced force to 1.0 mm short of the working length.