Pre op xray separated in file in place
File was separated during cleaning of the canal. Evidently it could not be removed or practitioner did not have the instruments to remove it.
Final post op completed RCT
Please note slight curve at the end of the root with a lateral canal going toward the distal.
Magnified view of post op apex
Separated instruments in the upper third of the root system can generally be removed with ultrasonics. Separated files further down the system, especially around curves, are just about impossible to remove. It is not the file that causes post operative problems,but rather, a canal system that was not cleaned properly and blocked by the file.