Progression of the files is done by applying slight apical pressure
• Frequently remove the file, inspect the blade for obturation material and clean the debris from the flutes
• If the rotary file can not go deeper, use a hand file to overcome the resistance and confirm the canal permeability
Protaper Retreatment files have been designed to remove filling material before canal re-shaping.
D1 File : With working tip to facilitate initial penetration.has a cutting tip to facilitate initial penetration into the filling material.
For coronal filling removal
D2 and D3 File: Both have non-cutting tips and are used to remove material from the mid and apical thirds, respectively.
D2 for middle filling removal
D3 for apical filling removal