(PR042) Factors Affecting Success Rates for Bypassing Fractured NiTi Rotary Instruments in a Pilot Study Involving Students and Faculty in a CODA-Accredited Dental School

Objective(s): A potential complication that new graduate dental practitioners may encounter is rotary file separation. One approach in addressing separation is bypassing the separated file. While prior publications have examined the factors contributing to a successful bypass, it is hypothesized that prior experience is a critical factor in determining the success rate of being able to complete a successful bypass of a separated file.

Methods: Extracted teeth with intact apices were collected and root curvatures were assessed by radiographs. Fractured F2 WaveOne Gold rotary tips were embedded in the apical portion of prepared root canals. Mounted teeth and radiographs were randomly distributed to participants consisting of dental students and endodontic faculty from a CODA-accredited dental school. Successful bypass was defined as inserting a file past the original apex within the canal without irreparable complications. Time used to bypass the separation was recorded and results were verified by radiographs. Questionnaires regarding procedures were also distributed.

Results: Twelve samples distributed to participants showed a three-fold increase in more bypass successes with faculty than with students. Average time used by students was more than double than that by faculty. Significant statistical differences were found (ANOVA, p<0.08)(2.37). According to questionnaire results, lack of prior experience was recognized as the biggest challenge.

Conclusion: The presented pilot study suggested within student groups that provider experience is a key factor for separated file bypass despite limitations in the study’s sample size. Other factors may also contribute to separated file bypass success but require further study.