When the rotary instruments removal method is utilized, select the lowest speed (250-300 rpm) similar to other rotary files, that will effectively engage and remove obturation material from the canal. 1)Flood the pulp chamber with the appropriate solvent and probe the canal orifice with an explorer to check if the paste has been effectively softened.
2)Without engaging dentin, gently press the spinning D1 File into the material and use a short pecking motion to extract material out of the canal. Never engage D1 around a canal curvature.
3)Remove the D1 File frequently, inspect the blades for obturation material and clean the debris from the flutes.
4)Continue with the D1 File, until paste is removed from the coronal one-third of the canal.
5)Select the D2 File and repeat the same packing action to extract obturation material from the middle one-third of the canal. Use a brushing outstroke motion to remove material from the canal walls.
6)When appropriate, choose the D3 File and, in the same way auger the more deeply positioned paste material out of the apical one-third of the canal. endodontic instruments
7)Continue with the D3 File as long as the flutes of the instrument, upon removal, are loaded with obturation material.
8)When the obturation material is short of the canal terminus, use small sized hand files in the presence of a viscous chelator to negotiate and secure the rest of the canal. 9)After assessing the glide path, select either manual or protaper rotary Files to shape and finish the canal.
therefore, ProTaper Retreatment Files=D files=RT files is very necessary in rotary instruments, it plays an important role as well.