The file is in the MB#2 canal. (Pic 1)Since it is in the upper third of the canal, good visualization with a microscope and proper ultrasonic technique will make this file removal possible.
After finding the file, (Pic 2) careful ultrasonic instrumention is used to remove dentin around the file – opening up the MB groove. This is done carefully without touching the file itself. We want to expose 2-3 mm of the file before we begin vibrating the file itself.
Too much contact with the file in this early stage can cause a coronal piece of the file to break off, making it more difficult.
Once the coronal coronal 2-3mm of the file has been accessed, (Pic 3) the ultrasonic is placed on the most apical part of the file to begin vibrating it. This should loosen the file and vibrate it out. If the file breaks again, then repeat step one.
The file was removed and the MB#2 canal instrumented.
Removal of the separated instrument complete.
Use of an operating microscope is essential in effective removal of a separated instrument.