Case of lentule fracture. Patient sought the specialization clinic reporting previous endodontic treatment in a tooth 11, whose professional reported that there was instrument fracture and impossibility of continuing treatment. In the radiographic exam it was observed a fractured instrument inside the canal in all its extension, compatible with lentule fracture. After isolation and access, the removal of the instrument was attempted with the apprehension of its tip with a Stieglitz forceps, without success, due to the locking in the medium and apical region, even with the application of moderate and more intense force. It was then decided to try to go beyond and enlarge the canal, which was successfully accomplished. However, the instrument did not unlock. It was then performed a protocol of irrigation and obturation in the working length.
The case alerts to the care and respect for the kinematics of the endodontic instrument and its speed and torque parameters, as well as the caution not to insert instruments not designed for this purpose.
The endodontic instruments, whether manual files, rotatory or reciprocating files or lentils and irrigation instrument and degates or Largo burs, can fracture inside the root canal in any region, apical, medium and cervical. If the speed, torque and other parameters such as type and direction of rotation are not respected, besides the incorrect use, there will be risk of separation of the instrument, often difficult to remove.
The first choice is to remove the instrument and then treat it with different apparatuses and techniques, but this attempt is not always successful. One of the solutions, when it is not possible to remove the instrument, is to exceed the working length of the instrument and irrigate and fill it up to this limit, with subsequent follow-up and instruction of the patient.
In case of failure in any technique, it is then indicated the paraendodontic surgery for resolution via apex, removing the instrument and performing retropreparation and retroobturation.
