One Way to Interpret The Successfully Treated Teeth With Separated Instruments Here On Linkedin

It dawned on me that while I find the cases of separated instruments that other dentists and endodontists are posting quite impressive and in some cases miraculous that such cases do not reflect the incidence of instrument separation. Rather, they represent the cases that clinicians either successively removed the fragments or negotiated around them. No one is posting cases where the segments remained or were unable to be negotiated around.

I mention this insight because separated instruments to this day are a cause of lower success rates when employing instrumentation systems that are prone too breakage as canal anatomy becomes more complex. So, in a sense, information that is relevant to our decisions on what systems to use, is hidden in plain sight simply by observing the cases that have been successfully treated and reported here on linkedin.

So when I see the successfully treated cases posted here on linkedin there is no question that they are impressive and the practioners achieving such results are to be commended. What it further tells me, however, is that we should be paying more attention to avoiding such iatrogenic events in the first place. By avoiding such events, it can only aid in improving endodontic results overall. That has been my mindset since I first became acquainted with rotary NiTi years ago and the increased incidence of unpredictable instrument separation that I became acquainted with.

As anyone familiar with the posts I place here on linkedin know, employing 30o oscillating stainless steel relieved reamers at high frequencies limits the arc of motion to 1/12 that of full repetitive arcs of motion that in turn diminishes both the torsional stresses and cyclic fatigue to the point where they can no longer induce instrument separations. In short, used in such a way, instrument separation is completely eliminated. Dentists should be aware that the same short arcs of motion engine-generated by the 30o oscillating handpiece have the added advantage of staying true to the original canal anatomy and being engine-driven also eliminate hand fatigue and excessive time requirements. It should also be noted that in accordance with Newton’s Third Law of Motion instrumentation systems immune to breakage are also far less likely to induce dentinal micro-cracks.

So given these advantages and their potential to lower the procedural stress level, why are they not employed more often? For one, most dentists via the education they received in dental schools have never been exposed to this alternative form of instrumentation. For those who gain insights here on linkedin they are also exposed to one critic in particular who is consistently referencing studies that the 30o oscillating stainless steel relieved reamers are causing more distortions and doing a poorer job at debridement than their rotary NiTi counterparts. In responding to his references, I have taken a variety of different tacks including:

. Posting numerous cases that appear to shape even complex pulpal anatomy without any apparent signs of distortions

. Posted cross-sections of instrumented and obturated highly oval canals that show no signs of debris left behind

. A video of a 3D printed mandibular molar where the canals and the isthmuses are fully debrided via the oscillating reamers

. A French study that clearly shows that the oscillating reamers rendered the canal walls free of the smear layer that rotary instruments routinely produce that in turn is a barrier to the penetration of interim medicaments and endodontic sealers into the dentinal tubules.

. Most recently, I have posted dialogues with the AI system GPT-4 that corroborates that the mechanics involved in this alternative approach are not only logical, but represent solutions to the short comings of rotary NiTi systems that are inherent to them.

So, it would mean little if in preventing instrument breakage, I suggested the use of an alternative system that had the downsides of distortions and ineffective debridement or was simply to cumbersome to employ. On the contrary, it makes no sense for a study to claim superior debridement by a rotary system that must stay centered to prevent separations to one that is vigorously applied to all the canal walls and activates the irrigants by stainless steel reamers oscillating at 3000-4000 cycles per minute as they drive the irrigants into intimate contact with the canal walls. It is also proven that the 30o oscillating reamers as confirmed by GPT-4 AI is a more effective way of delivering the balanced force technique that is utilized to shape curved canals without distortion.

Perhaps, some can relate to my puzzlement why anyone without opposing commercial interests would object to anyone observing and commenting on the skills of those who have successfully treated cases with separated instruments and also suggesting ways to avoid the problem in the first place. The critic commented that my doing so was hijacking those who post such cases. I believe he doesn’t appreciate the purpose of the forum we are on, to expand our knowledge, improve critical thinking and gaining insights from others that we can then evaluate on its merits. And, in fact, I have received thanks from those who I have made these comments to.

The reality is that instrument separation can be completely eliminated simply by limiting the arc of motion of stainless steel relieved reamers to 30o regardless of the complexity of canal anatomy. That seems like information that should be widely dispersed. And where it is not, you can be sure corporate influence is controlling the educational environment unfortunately with the required cooperation of school administrators. A harsh statement, but given the study by Rhodes published in the November 2021 issue of JADA that 80% of academic endodontists are the recipients of industrial payments, something that would not be possible without the permission of school administrators, is consistent with programs more effective as indoctrination rather than education.

The insights I am gaining from my ongoing dialogue with GPT-4 are eye opening and I recommend anyone interested in participating in discussions free of bias and hidden agendas experiment by asking this AI system questions that come to your mind.

Regards, Barry