File removal depends upon the position in the canal, canal curvature, access and patience (you need lots of this!). It is most difficult to remove files that have separated beyond the curvature and close to the apex. All of these cases below were made possible with the use of a stereomiroscope for fine vision and magnification.
Note separated file in mesial canal
File removed and obturated to length
4 month review and healed well
The next example is of a file tip separated just before the curvature. It is most important not to perforate while attempting removal in those canals with sharp curvatures
Separated file in mid-root of canal
File removed and canals obturated to length
Let’s be honest, if you haven’t separated a file in a canal you haven’t performed a root treatment. It happens! Now, the thing is with a bit of knowledge and skill (and luck!) you can remove the separated file tip beyond a sharp curvature without perforating the root.
File separated past curvature
File successfully removed
Image of file tip removed
The last case shown below is of a Lentulo or paste filler file separated in a premolar tooth. The paste filler file that has separated is challenging to remove due to the inherent spring coil design. Once the file separates, the spring engages into the canal wall and makes its delivery more difficult.
Lentulo or Paste filler file separated near apex
File removed successfully and obturation completed to length