Evidence Based Orthodontics

Welcome back. This segment is entitled Evidence-Based Dentistry/Orthodontics and the Need for a New Paradigm. In dentistry, we've been talking about evidence-based treatment for the last 15 to 20 years, and it's something that's discussed routinely at orthodontic meetings and in dental meetings. But let's really explore what's evidence-based and what isn't. Let's first look out of the Journal of the American Dental Association in 2009. Take some quotations from there. Here it states, a review published 14 years ago suggested that most treatment decisions in dentistry were made in the absence of accurate information about outcomes of treatment alternatives. In the intervening years, the advent of the systematic review has demonstrated even more clearly the paucity of evidence about the effectiveness of dental treatments. In the absence of clinical evidence, evidence-based guidelines for treatment of specific clinical conditions either cannot be promulgated or are based on the lowest level of evidence, expert opinion, which is most vulnerable to bias. To some extent, the profession's underdeveloped knowledge of the outcomes of dental treatment is an artifact of its historical reliance on the observations and the opinions of experts. Although most, but not all, new dental treatment interventions have been supported by the results of at least some outcome studies, dentistry has a legacy of traditional treatments and protocols that have not received the same scrutiny. Here's out of an orthodontic journal from 2010, written by a head of an orthodontic department. When no evidence is available, how does the clinician make decisions? Frequently, the cold, hard facts of science are up against the dreams, aspirations, and warm rhetoric of the latest techniques with their beautiful brochures and unsubstantiated claims. This could apply to Class II correction techniques, temporary anchorage devices about which 3,500 articles are available and still not a single random controlled trial, and self-licating brackets for which RCTs and systematic reviews show minimal to no advantage over conventional brackets. Or how about centric relation? This quotation from the Journal of American Dental Association. There appears to be little benefit of using gnathological records and articulator-mounted dental casts to discern MI/CR discrepancies in orthodontic patients. Cuspid-protected occlusion as the optimal type of functional occlusion to establish in orthodontic patients is equivocal and unsupported by the evidence-based literature. The stability and longevity of cuspid-protected occlusion is questionable. How about the facebow? Conclusions: In this study, there was no evidence to suggest that using a facebow transfer improved the result of complete dentures, occlusal bite splints, or planning orthognathic surgery. Undisputed clinical evidence and an online video justified eliminating the use and teaching of the facebow transfer. Here's another one: The ideal posterior occlusion concepts as a general orthodontic treatment goal should be reconsidered. That's from 2011. And here, from the American Journal of Orthodontics in 2009: Let's consider an even thornier issue. Although the concept of ideal occlusion has taken precedence as the ultimate goal in clinical orthodontics for some 110 years and serves well as an adopted arbitrary convention and a clinical gold standard, it has no verifiable scientific validity. No one has yet demonstrated that ideal occlusion provides significant benefits in oral or general health, or that it significantly improves oral function. By the same author, another study, Another article, rather. In the past 100 years, no one has been able to produce scientific evidence to corroborate Bonwill and Angle's original hypothesis. Occlusion is no more a science today than it was in the 19th century. In spite of this flawed conceptual underpinning to orthodontics, ideal occlusion is likely to remain the most fundamental concept in orthodontics until a new and hopefully more scientific paradigm replaces it. Ideal occlusion has served as a highly useful arbitrary standard for judging the skills of orthodontists and is still the major tool used by the American Board of Orthodontics for ascertaining board qualification. Thus, it is fair to say that orthodontics has been more technologically driven than biologically or scientifically based. Now, let's look at the whole concept of stability from the University of Washington studies. This is from October 2009. The University of Washington has the most long-term studies on stability of lower incisor alignment. Here it states, the idea of balance and stability is more a hope and myth than a reality. It further states, adults seem to have a few unique problems, such as slight space reopening in extraction sites. This may be due to non-parallel roots of teeth adjacent to the extraction sites, It can also be due to excessively rapid space closure. Nowhere in here, by the way, does it mention anything about reduced tongue space and the fact that the tongue might be pushing the teeth forward to regain its tongue space in the cases where retraction has been done. So, this study concludes, also from the University of Washington, Little's study in 1988, that 20-year post-retention, only 10% of the patients have acceptable alignment. I show this picture here along with the airplane over on its side, essentially saying if we had less than a 99.999% safety record, the FAA would ground all airplanes. And yet we have a 10% acceptable alignment, and people line up to have their next child treated with the same traditional orthodontic treatment. What I'm saying to you is that the retractive model of orthodontics is outdated and never was supported by evidence-based science, as you've just seen. We need a new paradigm for orthodontics, and I propose that it would be for development of the face and optimization of the airway. And I believe that this is supported by anthropologic evidence and common sense. Here's the anthropologic evidence we've talked about from Dr. Daniel Lieberman at Harvard University, talks about how our faces are down and back from where they were in our ancestors. John Muse shows the Paleolithic profile and shows where the Steiner norm is. The Steiner norm would have SNA be at the position you see in the red line, dramatically back from where the Paleolithic norm would be. The McNamara norm would be approximately there, still dramatically recessed from where the Paleolithic norm would be. And here you see the Paleolithic norm. Now imagine what a person with a soft palate hanging off of the back of this— of the hard palate is with the Steiner norm versus the Paleolithic norm. That airway is dramatically decreased the farther back the face is. The same with the mandible being back. The farther back the mandible is, the smaller the airway is. The point is, we're dealing with people today who have maxillas and mandibles that are dramatically too far back, and talking about straightening their teeth for them, essentially all we're doing is rearranging the deck chairs on the Titanic. We need to get real about this. Michael Gelb has gotten real about this and authored this article on airway-centric TMJ philosophy. In this article, he states that the airway governs our ability to breathe and to achieve a restful, oxygenated, restorative night's sleep, as well as to perform optimally during the day. Any TMJ or occlusal philosophy must address airway patency while managing pain and dysfunction, identifying contributing factors, and alleviating perpetuating factors. The teeth are the last piece of the airway-centric paradigm. The airway is the first, then the joint and muscle, and lastly, the occlusion. In other words, what Michael Gelb is saying, if you don't fix the airway, nothing else gets fixed. What does it mean to have airway-centric orthodontics, which is a term that Michael has trademarked and given me permission to use? Basically, it means that you don't want to decrease the airway even minutely, and it also would mean that ideally, we would be doing treatment which would actually increase the airway. The American Dental Association has finally gotten on board with this and talks about dentists doing treatment. Dentists can and do play an essential role in the multidisciplinary care of patients with certain sleep-related breathing disorders and are well positioned to identify patients at greater risk of sleep-disordered breathing. Let's go further to the scientific literature, and Dr. Christian Guilleminault from Stanford University Sleep Center talks about the elimination of oral breathing. In other words, the restoration of nasal breathing during wake and sleep may be the only valid endpoint when treating sleep apnea. Preventive measures in at-risk groups, such as premature infants, and uses of myofunctional therapy as part of the treatment of OSA are proposed to be important approaches to treat appropriately sleep-disordered breathing and multiple comorbidities. From the European Respiratory Journal, this large community-based pediatric cohort confirms earlier findings highlighting a significant impact of sleep-disordered breathing on behavioral regulation, with the greatest impact being already apparent among habitually snoring children. And why are they snoring? Because their airways are compromised, because their faces are back. We need to understand this. Our findings do support the need for considering early intervention, particularly among those children manifesting behavioral impact of sleep-disordered breathing. Here's Karen Bonnick's study conclusions. In this large population-based longitudinal study, early life sleep-disordered breathing symptoms had strong persistent statistical effects on subsequent behavior in childhood. Findings suggest that sleep-disordered breathing symptoms may require attention Early as the first year of life. We also know that ADHD is a huge thing now, with— we're now— doctors have diagnosed ADHD in about 15% of American children, and they routinely prescribe stimulants such as Adderall and Ritalin to help kids focus and concentrate. Dr. Stephen Sheldon from Lurie Children's Hospital in Chicago states that He believes ADHD does not exist. It is a sleep and breathing problem in all cases, he indicates. And why is that sleep and breathing problem the issue? Because the jaws are too far back. Here we have another article about pediatric obstructive sleep apnea and the critical role of orofacial growth. And it states that pediatric sleep apnea is, in non-obese children, is a disorder of orofacial growth. The bottom line is, the jaws are too far back and the airway is compromised. So, this article is published in Cranio in 2017, is a follow-up to Michael Gelb's article, written by, by me and Michael Gelb. Here it states, airway-centric TMJ philosophy and airway-centric orthodontics ushers in the post-retraction world of orthodontics. For those of you interested, in providing better airways for your patients. The specifics are in this article. I highly advise you to read it. So, basically, when we really look at it, there's not much evidence to support orthodontics as it currently is. And obviously, we need a new paradigm, and I propose that that paradigm would focus on facial balance and airway optimization as being the ultimate goal of orthodontic treatment, not getting straight teeth.