Sleep-disordered breathing (SDB) affects adults and children worldwide and previous studies (HypnoLaus study), which found rates of 49.7% for men and 23% for women.
This is huge. A 2019 U.S. paediatric study reported that an estimated 1% to 5% of children have sleep-disordered breathing related to obstructive sleep apnea, with a smaller proportion of children having central or mixed sleep apnea and goes on to state the benefits of screening, diagnosis and treatment.
In my opinion, this group (children) are both the group that when treated would have the greatest long-term benefit to society, yet are also amongst the worst served groups.
It is estimated that approximately 23 million adults in the United States alone have undiagnosed or untreated moderate to severe obstructive sleep apnea (OSA), basically road accidents (2-10% increase), emergency or hospital care, and the enormous financial burden on healthcare resources.
The same is certainly true in Canada and the UK where just like the US, the present government quietly pass the problem to the next government while the patients simply continue to enjoy their increased morbidity and mortality.
The main problem in patients with SDB/OSA is the pharyngeal or upper airway collapse occurring in hypopnea (partial closure following collapse and reduction in ventilation) or apnea (complete respiratory cessation).
According to the famous researchers Guillerminault and Huang “the upper airway is a collapsible tube, and its collapsibility increases during sleep”. That is the crux of the problem. Our increasing weight as a population, merely worsens the outlook.
The increased levels of carbon dioxide (hypercapnia) and the low concentration of oxygen (hypoxia) in the blood in these patients may lead to hypertension, cardiac diseases, and even premature death.
Other issues including snoring, mood disorder, disruptive, and depletion of quality of life are associated.
Some oral anatomic features associated with SDB may include high arched or narrow hard palate and retrognathia. This is both a cause and an effect.
The most common risk factor for sleep apnea in children is the airway constriction associated with enlarged tonsils and/or adenoids.
Additionally, the atypical jaw and facial growing pattern of what’s referred to “adenoid facies” has been associated with SDB, and may lead to a reduced size of the upper airway; causing not just sleep breathing-related problems but also a constricted maxilla, usually causing posterior cross-bites and crowded teeth.
Impaired growth, cardiovascular problems, and learning and behavioral problems are also linked to SDB, because these problems are critical and are related to craniofacial proportions, the dentist is the first person to recognize these issues.
The approach most often indicated to treat SDB in adults is the oral appliance (OA). The OA can be categorized into two types, mandibular advancement device (MAD) which aims to protrude the mandible and associated soft tissues to open the airway and reduce the apnea-hypopnea index (AHI).
This is the measure most commonly used to determine success (airway compromise per hour).
The less frequently used tongue retaining device where the objective is to maintain the tongue in a forward position, to avoid obstruction of the airway may also be used, but is more frequently retained for those without teeth as the others require teeth to hold the jaw.
However, continuous positive airway pressure (CPAP) therapy is mostly used by sleep physicians as the gold standard for OSA management because it almost always works if the patient can tolerate it.
Oral appliances exist because many people cannot tolerate CPAP, and many choose not to. Alas, many times those patients are often offered no alternatives due to ignorance, arrogance or financial incentive.
For years, many studies reported upper airway dimensional changes and AHI decrease in children and adolescents with posterior cross-bites (upper teeth biting outside the lowers) and/or maxillary constriction (narrow dental arch) and retrognathia (lower jaw anatomically further back than the upper, treated for maxillary expansion and mandibular advancement, respectively.
In general, those studies, have encountered positive results in regard to an increase in upper airway dimension and breathing capacity. An increase in the upper arch width (rapid maxillary expansion) has been shown to be a worthwhile procedure WHEN indicated, just as has Adeno-tonsillectomy.
Although it is evident that dentists have an important role related to SDB/OSA, the exact position of the dentist in the overall evaluation and treatment paradigm for patients with SDB/OSA continues to be debated. It will be for the individuals to determine how we’re seen as a whole.
The objective of this systematic review was to summarize existing guidelines, recommendations, and studies designed with the intention to describe and guide the role of dentists in SDB related issues.
Abbreviations
SDB: sleep-disordered breathing. This is the syndrome of signs and symptoms of airway compromise during sleep. This includes snoring, obstructive sleep apnea (mild, moderate and severe) and UARS – upper airway resistance syndrome.
OSA: obstructive sleep apnea. The disease of airway closure (part or full) during the night caused by an obstruction.
OAT: oral appliance therapy. A dental appliance constructed to maintain an open airway by either, or both jaw repositioning and airway protection from the tongue.
MAD: mandibular advancement device. An oral appliance which repositions the jaw relationship (lower to upper) thereby protecting the airway from intrusion of the tongue. It may be seen as a ‘mechanical stent” to keep the airway patent.
AHI: apnea-hypopnea index. The combination of partial and complete airway closures per hour from which the diagnosis and management success is determined.
CPAP: continuous positive airway pressure. This is a means of delivering room air (often humidified) at pressure. It is generally composed of a bedside pump, hose and face mask. It may be seen as a ‘pneumatic stent” to keep the airway patent.
AADSM: American Academy of Dental Sleep Medicine. The largest association of dentists with a special interest in dental sleep medicine. Examinations are available for advancement.
RDI: respiratory disturbance index or respiratory distress Index — is a formula used in reporting polysomnography (sleep study) findings. Like the apnea-hypopnea index (AHI), it reports on respiratory events during sleep, but unlike the AHI, it also includes respiratory-effort related arousals (RERAs).
RDI is calculated as the number of apnea events/hour plus the number of hypopnea events/hour plus the number of respiratory-effort related arousals (RERAs) per hour of sleep.
UARS: Upper airway resistance syndrome – see UARS article.