Temporomandibular Disorders and Sleep Apnea

A study in the Journal of Orofacial Pain examined patients diagnosed with sleep apnea and found that 52% of the patients with mild to moderate sleep apnea had symptoms of TMD. The primary problem was myofascial pain that was sometimes related to jaw opening. The idea that jaw relations can cause sleep apnea has been well accepted and the NHLBI has published a report “Cardiovascular and Sleep Related Consequences of Temporomandibular disorders. The authors recommend that these patients should be evaluated specifically for treatment of TMD. Oral Appliances have been claimed to cause bite changes and jaw problems. If the jaw problems pre-exist the oral appliance therapy then we must change our view of the process. I propose that the bite changes that are seen with use of mandibular advancement devices (MAD) is actually a healing mechanism that occurs when the TM JOINT is unloaded and the retrodiscal lamina in the posterior portion of the joint rehydrates and acts to mechanically change the bite. If this is considered a state of healing we then must reconsider the entire concept of Centric Relation. Centric Relation is a concept where dentists manipulate the jaw to find a hinge axis position and then use that position to establish the bite. There is an old belief that the jaw functioned in a purely rotational manner in that position. Research has proved that to be incorrect. The term Centric Relation is not well understood by most dentists and there have been over 28 definitions of CR each giving a different position for the TM Joint condyles in the fossa. All of them are mechanical definitions of the proper joint position.

Neuromuscular Dentistry on the other hand restores the physiologic balance to the muscles and their neurological connections. The patients own muscles are returned to a healthy state and then the patients own muscles find the proper jaw relations. The basic concepts of Neuromuscular Dentistry were developed by Dr Barney Jankelson who changed how we look at jaw function from an old fashioned strictly mechanical model to a physiologic model based on healthy neuromuscular jaw relations that are not based just on TM Joints but rather on the entire human body as a physiological system. The proper relations of the jaws are detemined when the muscles are at their healthiest.

The position that Neuromuscular Dentistry allows the jaw to attain as the system heals is remarkably close to place that patients wearing oral appliances for sleep apnea and snoring treatment find their jaws naturally migrating to. Most dentists who treat sleep apnea, this author included give patients exercises to return their jaws to the original pathology. How do we know their original bite is pathologic? The single most important function orf the jaw, jaw muscles, tongue and entire trigeminal neuromuscular complex is to maintain airway and life. The utilization of CPAP to maintain life is basically a crutch to overcome a Temporomandibular disaster, the failure to maintain an airway. Froward head posture (actually forward neck posture) is a compensation to allow breathing is spite of pathological jaw position that closes the airway. Unfortunately we cannot use this compensation during sleep when our muscles go into a state of relaxation.

We must continue to ask the question why are we trying so hard not to change bites when we know this is a position of pathology in terms of airway. Why not let the mandible posture forward and heal in that forward position when oral appliances are used to treat sleep apnea? The study quoted above was wrong when it said 52% of patients treated for sleep apnea had TMD symptoms. Actually 100% had TMD symptoms if we just admit what the NHLBI has already stated “s;eep apnea is a temporomandibular disorder”

Much of his wok related closely to the work of Guzay and his Quadrant Thereom where the TM Joint and jaw function were seen as much more important to posture and all body function. Much of this knowledge goes back to the work of Sherington acknowledged as one of the most important neurological researchers of all time. Both of these incredible minds grossly underestimated the importance on posture of airway.

When we begin to look at the stomtognathic system as the key to controlling airway and therefore life we get a new respect for the importance of dentistry in maintaining health. The trigeminal nerve is often considered the dentists nerve and is responsible for controlling blood flow to the brain, swallowing, breathing and is a major portion of our proprioceptive system we understand why disruptions in that systemare responsible for migraine, tension-type headache, cluster headache and other neurological conditions. “Suffer No More: Dealing With the Great Imposter” a Sleep and Health story explains how TMD problems can disrupt or even destroy lives. Neuromuscular Dentistry is also explained in a Sleep and Health story. Patients looking for help with migraines and chronic daily headaches will find the information they seek at the I Hate Headaches site: www.ihateheadaches.org

Dr Norman Thomas is a Neuromuscular Dentist, Anatomist and Physiologist who has taken over the teaching of Neuromuscular Dentistry at the LAS VEGAS INSTITUTE making it truly a world class learning environment. He is also the President Elect of ICCMO, the International College of CranioMandibular Orhthopedics.

PubMed abstract
J Orofac Pain. 2009 Fall;23(4):339-44.
Prevalence of temporomandibular disorders in obstructive sleep apnea patients referred for oral appliance therapy.

Cunali PA, Almeida FR, Santos CD, Valdrighi NY, Nascimento LS, Dal’fabbro C, Tufik S, Bittencourt LR.
Aims: To evaluate the prevalence of pain associated with temporomandibular disorders (TMD) in obstructive sleep apnea syndrome (OSAS) patients referred for oral appliance therapy. Methods: Eighty-seven patients (46 men and 41 women), between 18 and 65 years of age, with an apnea-hypopnea index (AHI) of > 5 and < 30 (events by sleep hour), and body mass index (BMI) of =/< 30 Kg/m2 were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) to determine the presence of signs and symptoms of TMD. Statistical analyses included correlations assessed by Pearson's test. Results: Fifty-two percent of patients presented symptoms of TMD. Thirty-two patients (average age 47 +/- 11 years, AHI 17.3 +/- 8.7, BMI 25.9 +/- 3.8 kg/m2) completed the study. According to the Scoring Protocol for Graded Chronic Pain (Axis II-RDC/TMD), 75% of the patients presented chronic pain related to TMD, categorized as low disability grade I (< 50 points for pain intensity, and < 3 disability points). The most common TMD diagnosis was myofascial pain with and without limited mouth opening and arthralgia (50%). Conclusion: The high prevalence of TMD in the current study indicates that patients with OSAS referred for oral appliance therapy require specific evaluation related to TMD. J OROFAC PAIN 2009;23:339-344.