Dental Sleep Medicine - Hiding in Plain Site?

How many times have you looked into the oral cavity of a patient and noticed that your patient has massive tonsillar tissue, or a battered and red uvula, or a tongue so muscular and large that you wished your assistant had the strength of Hercules to hold it back and out of the way when you were working on your patient?

Have you ever noticed the prominent scalloping of the tongue on a patient and just looked past it? Or perhaps you had experienced the reaction of horror from your patient when you began leaning them back in the chair, and they insisted you not lean them back any further. Most of the time during my career, I just chalked it up to “that’s just the way it is.”

I noticed these things in my practice and never thought much about them until I started investigating the possible causalities of these findings. What they all have in common is that they are potentially signs of a Sleep-Related Breathing Disorder (SRBD). As defined by the American Academy of Sleep Medicine (AASM), SRBDs are “sleep disorders that involve difficulty breathing during sleep.” The most common SRBD is obstructive sleep apnea (OSA). A colleague from Sydney, Australia, Roger Price, recently brought the term Breathing Related Sleep Disorders (BRSDs) to my attention, which he has used for the past 30 years. He points out that the breathing or diminishment of breathing impacts the patient's effective sleep. Regardless of the term you wish to use, many people have some significant problems.

SRBDs or BRSDs have patients presenting with excessive daytime sleepiness, insomnia, sleep eating disorders, snoring, bruxism, sleep leg cramps, and restless leg syndrome, to name a few. It is estimated that approximately seventy million people experience sleep disorders each year. [i]

These disorders are medical conditions that can only be diagnosed by a sleep physician trained in sleep medicine. Typically, pulmonologists, ENTs, and neurologists will have additional training in this specialty. Still, those in internal medicine, cardiology, psychiatry, pediatrics, otolaryngology, and anesthesiology also pursue residencies and fellowships that can lead to a sleep medicine subspecialty. These individuals frequently attain board certification in Sleep Medicine.

So, what does all of this have to do with dentistry? I once wondered that question until I began investigating the daily challenges my patients presented in my private practice.

Patients or their significant others often complained about their partners’ snoring and wanted to know if I could help them before they killed their significant others. Many of these people slept in separate bedrooms because they could not tolerate the other person's snoring. I figured I could help with that and started creating snore devices. I was a “hero,” and it felt good—until the devices broke or the teeth began to shift. That put the brakes on things for me.

Then, articles began popping up in the various “journals” I read about the creation of mandibular advancement devices that could help patients with sleep apnea. Again, that would be easy: take a couple of impressions and send them off to the lab, get it back, and adjust the devices until the patient said they weren’t snoring any longer. Some devices had polymer-elastic bands that would hold the jaw forward and allow the patient to move their jaw sideways as needed. I explained to the physician I worked with that this would greatly help their patients.

Then, the problems with the “bands” connecting the upper and lower devices began breaking with some devices. Too often, the sounds associated with the snoring they were having were not reduced as the devices were advanced, and again, the teeth began to move, and the joints began to hurt. To make matters worse, the secondary sleep studies that the patient had, as required by the physician, did not show improvement in the patient’s results. What did I get myself into?

What seemed so simple became a nightmare. I started investigating different types of devices that claimed to be the solution to my problems. I was told those would work. But alas, there was no improvement. The sleep physician called to say that she could not send any more patients to me since the secondary polysomnograms did not show improvement. I had “egg on my face.”

As I investigated the science of dental sleep medicine, I learned that my methodology used, George Gauge™ (GG), was not an exact science and could not provide a consistent outcome as I presumed it would. The method instructions for creating the devices are very explicit in the document “Where the correct construction bite” [ii]: “The optimum position of the construction of bite varies in each patient. It is somewhere between centric relation and full protrusive. There are no landmarks that can be used to locate it accurately. No relationship of upper-to-lower incisors can be correct for all patients.”

So, what does that mean? Unfortunately, this method is a guessing game. Many publications have indicated that there is an inherent problem with this methodology. In the article Retrospective comparison of the George Gauge™ registration and the sibilant phoneme registration for construction of OSA oral appliances[iii] the authors state: “The George Gauge™ Registration (GGR) has become a standard method used to document MA (mandibular advancement). Notwithstanding that GGR overestimates measurements of advancement when compared to a ruler and cephalometric measurements.” They continue with “the literature regarding optimum advancement is also conflicted, some determining optimum benefit with 70% advancement and others finding no benefit beyond 50% advancement.”

Hamoda et al.,[iv] states that the long-term effects of Oral Appliance Therapy (OAT) are maxillary incisor retroclination and mandibular proclination and that the changes seemed to continuously progress with time. Hu and Comisi[v] demonstrated in their study that the position determined with the 70% George Gauge was, on average, 5.0 mm more protrusive than positions found using an alternative position-determining device called a pharyngometer.

Pharyngometry is an analysis tool used to determine the optimal treatment position of an OAT when treating obstructive sleep apnea. It aids in identifying the location and severity of pharyngeal obstruction via the analysis of the minimal cross-sectional area (MCA). This minimally invasive testing mechanism can help screen patients suspected of suffering from OSA. After a sleep physician renders a diagnosis, it can help determine the optimal jaw position for appliance therapy. It can also be a significant asset in determining, before creating an oral appliance (OA), if the patient would be a responder using an OA.

Understanding whether a patient will respond to therapy is critical. All too often, when GG creates devices, there is no way of knowing if the device will be effective until it is created and worn by the patient.

Unlike GG, pharyngometry employs acoustic soundwaves that travel down the patient's airway in a non-invasive manner to help identify where the problem in the airway might be and determine the most beneficial and therapeutic position for an oral device. This typically is found with the help of special Airway Metrics jigs (Kettenbach USA, Huntington Beach, CA) that can help determine therapeutic position by opening the vertical bite at 4, 6, 8, 10, and 12 mm while using the pharyngometer. Typically, most devices I create are at an edge-to-edge position in this vertical dimension. If advancement is needed, these jigs can also help place the jaws in those positions while working with the Pharyngometer. Ultimately, this process places less stress on the TMJ area and enhances the patient's compliance.

The literature is currently filled with evidence of the benefits of incorporating this methodology for creating a device when treating patients referred to your office to fabricate an OA.[vi]^{,[vii],[viii],[ix],[x],[xi]}

But this was just the beginning of my journey. I began learning about the dental signs of SRBD and incorporated enhanced screenings into my practice. We found out that the bruxism we were attempting to treat could be traced back to sleep issues, and placing a mouth guard to protect the teeth could be closing off the airway.[xii] This also changed things for me; when I examined a patient with an apparent bruxing issue, I would always inquire about sleep issues. This requires you to be a real investigator, but it is worth it. Even more has been published on this issue.[xiii]^{,[xiv],[xv],[xvi]}

Now, for every patient I examine, I inquire if there is a history of sleep issues, a diagnosis of sleep apnea, snoring, and excessive daytime sleepiness. If they affirm any of this, a single arch flat plane splint will not be fabricated. Typically, I will refer to a Sleep Medicine specialist and request an evaluation and a sleep study to determine and render a diagnosis. If the diagnosis of obstructive sleep apnea is rendered, and a prescription for the creation of an oral appliance is provided, I will then move forward with the fabrication of a custom therapeutic device using pharyngometry.

Please remember that these Breathing Disorders (BD) are medical diseases and a prescription from a sleep physician is needed to care for all patients with OSA. The days of making snoring appliances, flat plane mouth guards, and unquestioningly creating sleep appliances are gone from my practice and what I teach, first as a faculty member at the Medical University of South Carolina and now at The Dental College of Georgia. The physicians I have worked with and the students I teach and will teach now have a greater understanding of the partnership between dentistry and medicine in this arena. Our students are all gaining further insights regarding the need to screen all patients for potential BD. This way, more people will be screened and ultimately treated for this ubiquitous medical disease. We are on the front lines. Now it’s your turn to learn more about it and help all of your patients you did not previously recognize as presenting with this problem.