Self-adjusting file (SAF) separation in clinical use: A preliminary survey among experienced SAF users regarding prevalence and retrieval methods

CONTEXT: The self-adjusting file (SAFs) is reported to be resistant to file separation in laboratory tests. No information is currently available regarding SAF separation during clinical use. AIM: To conduct preliminary clinical survey among experienced SAF users in order to establish the prevalence of SAF separation during clinical use and to study how were such cases treated. MATERIALS AND METHODS: A questionnaire was sent to experienced SAF users to make inquiries regarding incidence of SAF separation and how were such events treated. Only responses from operators who had used 50 SAFs or more were included in the present study. Fisher's exact test was used to compare file separation occurrence. RESULTS: A total of 2517 SAFs had been used by these operators, and 15 cases of file separation were reported (0.6%). Twelve of these 15 separated files could be retrieved within a few minutes using Hedström files, with no additional dentine removal required. In the three cases in which the separated files could not be retrieved, the separated file segment was successfully bypassed. CONCLUSIONS: The SAF might separate during clinical use, but the incidence of such an event was low. In most such cases, the separated file segment was easily and quickly retrieved without additional removal of dentin.