airway Prosthodontics promotes a philosophy of “prevent, control, resolve.” If there is an airway issue, early intervention may prevent craniofacial, systemic, and neurocognitive abnormalities.
If the damage has been done, control the disease with appliances, CPAP, etc. Finally, never stop with control. Always offer a resolution strategy. This may include, most commonly, ENT surgery, orthognathic surgery, myofunctional therapy, and orthodontics.
Breathing disturbances routinely begin as anatomic alterations that revolve around the improper positioning and/or dimension of the maxilla. Dentists routinely forget that the maxilla provides the foundation for the nasal cavity. Positive changes in it can increase nasal volume, improve nasal airflow, resolve septal deviations and correct soft palate collapse.
An early pioneer in orthodontics, Robert M. Ricketts, fought for these airway prosthodontic principles in as early as the 1950s.
"Respiration and mastication are biologically inseparable. The nose is a regulator, a heater, a humidifier, a vacuum cleaner, a sterilizer and a primary sensory organ. The nasal cavity just happens to be formed by essentially the two parts of the maxilla which also happens to be the basal structure for the upper teeth and most of the upper jaw. The lower limits of the nasal cavity also happen to be the upper limits of the oral cavity. What affects one affects the other. It would appear that normal nasal breathing is conducive to normal growth of the maxilla and normal development to the occlusion of the teeth. The well-being of the whole child may be involved where mouth breathing is concerned, and the clinician dealing with conditions relating to mouth breathing must look not only at the specific condition he is being asked to treat, but at all related conditions as well. Therefore, it would seem that the time has come for the problem to be subjected to a multidisciplined team of clinicians who can, as a team, treat the whole child."
He went further to suggest that orthodontists must begin seeing themselves as oral health providers.
"From the environmental standpoint, total respiratory function has been the most overlooked factor in clinical orthodontics. The influence of the beliefs in the '30s and '40s--the concepts of genetic dominance and the conviction of limited skeletal alteration as a possibility in therapy--led to the concept of treating just the teeth instead of the face or the patient as a whole. Information collected on failures now seems to suggest evidence of corrected respiratory problems, and not just adenoids and tonsils, but the entire mechanism of any respiratory obstruction. I wrote on this in the '50s and '60s as well as the '70s, but the profession's majority still takes only lateral head plates and really only a few heed the airway problems. Most orthodontists and researchers in growth simply haven't looked at the nasal cavity as a vital vegetative part of the face. We talk about the oral cavity as if it is independent of the development of the first branchial arch and independent from respiration. Biologically, the functions of mastication and respiration have been connected with the same set of muscles and the same set of nerve paths. We can't separate them."
60 years later, many orthodontists, in my opinion, still have only a limited vision of the vital role that they can play in the health of our patients.
An important pilot study was published in 2011 that may assist in altering our existing paradigm. Ekuni and colleagues1 investigated the relationship between malocclusion and heart rate variability (HRV).
HRV is a marker for autonomic nervous system (ANS) function. Sympathetic and parasympathetic divisions of the ANS impact the heart rate. In a relaxed state, the variability between beats grows. While it is counterintuitive, greater heart rate variability creates an environment for improved body function, healing and mental relaxation.
Reduced HRV has been linked to heart disease, heart failure, hypertension, diabetes and depression. In their study, the researchers evaluated HRV in young subjects with and without malocclusion. By adding questionnaires on chronic stress and quality of life indicators, the study attempted to link malocclusion to both physical and mental health.
20 patients had normal occlusions and 17 malocclusions of which two were deemed severe (greater than 6mm overjet or less than 4mm overbite). The malocclusions were 18 percent Class I, 53 percent class II division 1, and 29 percent class III. The results showed that HR was significantly higher in subjects with malocclusion and parasympathetic (vagal) activity was significantly lower. There was also a positive correlation between HR and higher anxiety/stress.
This was the first study to focus on HRV and malocclusion. The next step for orthodontics would be to test HRV before and after orthodontic therapy.
The implication of this study was that their HRV would increase in variability and the subjects stress and health would improve. That needs to be proven in a controlled way. This study did, however, begin to validate the words of Ricketts from long ago. Orthodontic treatment should go beyond the obvious contributions to esthetics and function and begin to address the health of our patients.
1. Ekuni D, Takeuchi N, Furuta M, Tomofuji T, Morita M. Relationship between malocclusion and heart rate variability indices in young adults: A pilot study. Methods Inf Med 2011;50:358-363.
Jeff Rouse, D.D.S., Spear Faculty and Contributing Author