Endo file separation – good planning will mitigate the risks, and help deal with the consequences
Featured Products Promotional FeaturesPosted by: Dental Design 13th December 2022
During endo applications, when a file breaks, the first thing that needs to happen is that the patient is informed. A review published in 2021 found that the overall incidence of file fracture was 2.27% (this figure includes instruments for both rotary and reciprocating motion).[i] Low then, but with the fear of a complaint or claim being a primary cause of stress among the profession, anyone who delivers endodontic treatments must be prepared for this scenario.
The patient’s response will be key to what happens next. Even if they accepted the small risk of file fracture – a fact that you would recorded in clear, accurate and comprehensive notes – they won’t have explored howthey’d feel if it happened to them. If the procedure has been smooth and comfortable up to that point, and they have they felt well-cared for by the practice team, their trust in you will hopefully be intact, and they will be happy to proceed as per your clinical recommendations.
This means they will also be reassured that the incident was not the result of an error, and that you also did all in your power to prevent it. Of the range of circumstances that can cause file fracture, included are anatomical factors unique to every patient. For example, in very curved canals, which are often narrow, a highly pronounced angle on the curve can cause instruments to experience greater fatigue.[ii] Research also found that the “rate of file separation increases as the radius of (the) curvature decreases.”[iii]
If removal of the file is recommended and accepted, this is a highly-skilled procedure and generally the job of a specialist. If you are going down this route, it may be that you need to refer. For the patient, that means more time spent on dental appointments, more invasive treatment and potentially a new practice to get used to. This is why communication is so important, and they will need to be fully informed about the consequences of notgoing ahead.
Another option is to bypass the file, perhaps because to remove it would be too difficult, or that leaving the fragment it is unlikely to pose a threat to health. Patients often resist this course of action, though, not wanting something left in their mouth that could lead to problems further down the line. There are plenty of endo horror stories for people to peruse online and, although these may not be a wholly accurate representation of a complicated case, negative headlines stick. Should someone feel pain in the area of their root canal years later, they might return to the practice who delivered their treatment, believing they can attribute their discomfort to the piece of retained instrument.
A further option is, of course to have the compromised tooth extracted, so they don’t have to worry about it anymore. Opting for an extraction, when the original plan was to save the tooth, would be a disappointing decision to make, and one which could have a lasting impact on the relationship between patient and practice.
So how to mitigate the risk, and bring the (albeit) small number for file fractures down? Selecting premium tools is fundamental, but they also must be used correctly; one study concluded that the most important influence on file defect rates was the operator.[iv] Materials and technique have a mutually exclusive relationship – innovation in product development means techniques have to ‘keep up’, and new techniques have meant that manufacturers have had to raise their game, to offer endodontists the kind instruments and equipment they want to use.
Superior metal alloys have made root canals safer, by allowing the creation of files that are flexible enough that they can be pre-bent, yet heat-treatment during the manufacturing process means they are extremely fracture resistant too. Some systems may require fewer files to complete treatment, so less hand fatigue. The latest generation of files have further characteristics that allow them to preserve the morphology of the root canal, avoiding ledging and apical transportation while conservatively treating root canals with extreme curvatures.
These files can be used with equipment that can enhance safety even further, for example combined endo motors and apex locators that utilise technology to warn the operator of torsional fatigue, like a digital notification/navigation system. This can result in fewer fractures, even if the anatomy is challenging and the canals are narrow and curved.
According to one study, dentists have different experiences of file separation, also the experience “was found to differ… at different times for the same practitioner.”[v] Sometimes endo will defy even your own rules! Choose quality instruments that you know how to use, keep communication with patients open and honest and you will not only mitigate the risks, but deal with file fracture without too much stress.
For more on COLTENE, visit www.coltene.com,
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Nicolas Coomber COLTENE National Account & Marketing Manager
[i] Gomes MS, Vieira RM, Böttcher DE, Plotino G, Celeste RK, Rossi‐Fedele G. Clinical fracture incidence of rotary and reciprocating NiTi files: A systematic review and meta‐regression. Australian Endodontic Journal. 2021 Aug;47 (2): 372-85.
[ii] Br Dent J 204, 241–245 (2008). https://doi.org/10.1038/bdj.2008.152
[iii] Br Dent J 204, 241–245 (2008).
[iv] Parashos P, Gordon I, Messer HH. Factors influencing defects of rotary nickel-titanium endodontic instruments after clinical use. Journal of Endodontics. 2004 Oct 1;30 (10):722-5.
[v] Madarati, A., Watts, D. & Qualtrough, A. Factors contributing to the separation of endodontic files.
Br Dent J 204, 241–245 (2008). https://doi.org/10.1038/bdj.2008.152
