What The Critic Is Most Adamant In Denying

What the critic objects to regarding comparing the use of relieved stainless steel reamers in a 30o oscillating handpiece at a frequency of 3000-4000 cycles per minute to the traditional balanced force technique manually employing K-files is the claim that the former approach limits canal distortions more than the latter, eliminating hand fatigue and dramatically reducing time requirements as added benefits. If, this is indeed the case, the potential commercial impact is not the replacement of the original balanced force technique, but the replacement of rotary NiTi be it used in a continuous or interrupted manner as the dominant instrumentation system employed today. So, let’s examine in detail why this is the case.

. Rotary NiTi introduced a metal that is flexible enough to be used in a rotating handpiece to negotiate curved canals relatively rapidly. This is a distinct advantage that stainless steel except in its thinnest configurations does not possess. Consequently, where NiTi can be used in either continuous or interrupted engine-generated rotations, it was assumed that stainless steel could only be used by employing them manually with minimal arcs of motion. While their non-distorting potential is displayed via the application of the balanced force technique, it remains a manual technique, hand fatiguing and time consuming.

. As soon as rotary NiTi was introduced, it became apparent that rotation, be it continuous or interrupted subjects the instruments to increasing amounts of torsional stresses and cyclic fatigue as canal anatomy becomes more complex, that in turn leads to a greater incidence of instrument separation. So, while rotary NiTi was a vast improvement over the manual use of K-files, still used manually for the creation of the glide path, it brought increased risks of file breakage. Given the options of a system that speeds up instrumentation without inducing distortions, but prone to breakage compared to one that is far more resistant to breakage, but hand fatiguing and slow, rotary NiTi on balance offers more advantages. Productivity outweighs greater safety especially given a rotary NiTi marketing campaign that is continuously offering new versions of rotary NiTi that claim increasing resistance to torsional stresses and cyclic fatigue, namely a reduction in instrument separation.

. Now along comes the engine-generated version of the balanced force technique. The use of relieved stainless steel reamers that are significantly more flexible than their K-file counterparts, engine-driven at a frequency of 3000-4000 cycles per minute and confined to much shorter arcs of motion than those employed in the balanced force technique. Under these circumstances, the ability to negotiate curved canals is enhanced, the engine-generated 30o arcs of motion further reduce the potential for distortions and the high frequency with which they are employed eliminates hand fatigue throughout the instrumentation process. The key threat to rotary NiTi as the dominant instrumentation technique, however, is the fact that confined to such small arcs of motion, in addition to the already listed advantages, the instruments are completely invulnerable to breakage. It is this fact, included in the advantages that the high frequency 30o oscillations of relieved stainless steel reamers brings to the table that must be refuted by a critic who for whatever reasons is compelled to defend rotary NiTi as the dominant system. In that endeavor, he refutes all data that illustrates the benefits the 30o oscillating reamers, denies the conclusions that the GPT-4 AI system generates supporting the use of 30o oscillating reamers over that of rotary NiTi and finally and consistent with his long term behavior personally denigrates the person (me) who brings up this alternative approach.

Of course, there are advantages that derive from using a system invulnerable to breakage. And why is it invulnerable to breakage? Simply because the short arcs of motion limit the exposure of the instruments to excessive amounts of torsional stress and cyclic fatigue. The shorter the arcs of motion the less the stress, but not only to the instruments. Consistent with Newton’s Third Law of Motion, less stress to the instrument means less stress to the canal walls resulting in a lower incidence of dentinal micro-cracks that can coalesce and propagate into vertical fractures. From the dentist’s perspective, the fact that relieved reamers limited to 30o arcs of motion regardless of frequency are invulnerable to breakage makes procedural stress far less likely. The instruments are used multiple times with great cost savings. One no longer needs an expensive auto-reversing torque sensing motor and handpiece. Knowing the instruments will remain intact under all conditions gives the instruments great adaptability to all pulpal configurations. Unlike rotary instruments with a range of martensitic (flexible) and austentic (stiffness) properties that either offer increased resistance to cyclic fatigue and decreased resistance to torque or vice versa, the 30o oscillating reamers never engender excess stress of either and cannot be compromised by the condition of the pulpal anatomy that the instruments negotiate through. These are the claims I have been making over the years on linkedin. Today we have at our disposal an AI system that is a powerful tool in further clarifying these claims.

His last line of response is to reference comparative research studies that concluded rotary instrumentation performed better than the 30o oscillating reamers. Having the validation of the 30o oscillating relieved reamers approach by an unbiased AI system that has nothing to gain or lose by stating its conclusions, we can compare that to the reality of academic endodontics today first by once again referencing the November 2021 study by Rhodes published in the JADA documenting that 80% are the recipients of industrial payments. When I have referenced this study in the past, I have been accused of insulting an entire generation of endodontic faculty. I don’t look at it this way. Zero percentage of academic endodontists should be the recipients of industrial payments. The insult, if there is any, is on school administrators who accept such conditions and a hat’s off support to the 20% who do not accept such payments. The fact that school administrators determine which endodontic instrument system will be exclusively taught to the student body based on the highest degree of corporate sponsorship does not add credibility to the claim of an unbiased education nor to the research studies in these same schools that coincidentally produce results that support the systems the students are mandated to use. Trust is based on the consistent integrity of one’s actions. A trusted response is one where the recipients of that response believe this source is free of any influence that might introduce bias, corrupting the response in favor of vested interests. Without question, corporate sponsorship of academic endeavors has made trust a much more questionable issue and has debilitated the belief in unbiased so called “evidence-based studies” at least where commercial interests are at stake. The critic might deny these conditions exist today. Given the evidence that substantiates the penetration of corporate influence throughout academia where profits are tied to a product, it is willful blindness to state such conditions don’t exist to a high degree and does nothing to alleviate the problem.

The GPT-4 algorithm provides a vehicle that produces a dialogue between humans asking questions and a large language model that has the ability to access unlimited facts and concepts, digest and integrate them and then derive conclusions that are free of inherent bias and not only offer constructive advice, but ask penetrating questions. Now, I am using GPT-4 and am highly encouraged by its responses. For those who disagree with GPT-4’s responses, you are free to ask your questions and if you do post them please include the questions along with the responses.

Regards, Barry