Obstructive sleep apnoea

03 February 2011
Volume 27 · Issue 2

Matt Everatt reviews the role of the dentist in snoring.

Matt Everatt reviews the role of the dentist in snoring.

Almost everyone will encounter a sleep-related breathing irregularity, typically snoring, at some point in their life, whether they suffer themselves or are kept awake by a partner or co-habitee.

While most sufferers will dismiss the problem as merely an annoyance, for some, if it remains untreated, it can become a debilitating condition with a number of maleficient side effects. In serious cases the condition may worsen to become obstructive sleep apnoea (OSA), the most common category of sleep-related breathing disorder.

All dentists will be aware any activity within the oral cavity has a direct influence on air transit and so may be associated with snoring and sleep apnoea. Obstructive sleep apnoea is defined as the total cessation of the airflow into the lungs during sleep caused by an obstruction, resulting in gaps in regular breathing which provoke the sufferer to wake suddenly, often with a loud snore, a snort or a gasp. While a complete collapse of the pharyngeal airway induces OSA, a partial closure causes the air to vibrate as it passes through the throat, resulting in snoring.

Statistics, causes and diagnosis

A 1986 survey by Rice & Perskey revealed approximately 45 per cent of the UK adult population was affected by snoring, and it is now believed that this figure has risen to 75 per cent as a consequence of obesity. Snoring is known to have adverse effects on sleep quality, overall health and the quality of family life, and has even been cited in divorce cases. Far from being merely an annoyance, it needs to be taken seriously.

Obstructive sleep apnoea can range from very mild to severe, with symptoms varying according to the amount of stress experienced by the subject during the five stages of sleep. As sleep deepens muscles throughout the body become increasingly relaxed, which can cause the mandible to drop, compromising the airway and causing a distal motion of the tongue and soft palate. This is especially common when subjects sleep on their back. Prolonged apnoeas place the body under additional stress, and when breathing is interrupted the brain becomes starved of oxygen, causing blood pressure to rise as the heart rate increases to compensate. These factors contribute to the sudden waking of the subject, and as the body attempts to clear the obstruction the rise and fall of the abdomen may induce nocturia, a pressing need for sufferers to relieve themselves immediately on waking.

Treatment

Milder cases of snoring often respond to a healthier lifestyle, when the patient for example ceases smoking, loses weight or reduces his or her alcohol intake. The alleviation of more severe cases and apnoeas requires direct intervention, and although a wide range of products are available which claim to treat both conditions, experience suggests there are only two effective methods of treatment.

There is acknowledged empirical evidence that Mandibular Advancement Splint Therapy (MAS), the treatment already favoured by many dentists, is effective against snoring, while the most benefit for sufferers with sleep apnoea and OSA is presently achieved by the use of nasal Continuous Positive Airway Pressure (nCPAP) devices. However, although these devices are becoming more sophisticated and comfortable to use, many patients remain hesitant, and at present there is no widely approved alternative. There are a few clinicians in the UK prepared to treat patients whose apnoea condition does not respond to nCPAP treatment, or who decline its application, with MAS, but this multi-disciplinary approach requires the patient to take part in a sleep study to gauge the efficacy of the device.

It is imperative to ensure proper screening protocols are applied when diagnosing snoring or apnoeas. Current legislation prohibits dentists from prescribing MAS for OSA patients, as it is designated within the sole competence of a qualified medical doctor, but simple snoring can be relieved, immediately and effectively by a dentist, although a history of the patient must be recorded and correct procedures followed.

Dental Protection has issued guidelines to safeguard both dentists and patients:

'When a patient requests a dentist to provide an anti-snoring device, the dentist may comply providing the following conditions are met:

  1. The dentist has undergone a documented training course in the provision of anti-snoring appliances, which includes training in the appropriate screening for OSA.
  2. The patient has been properly assessed for the signs and symptoms of OSA in accordance with contemporary standards and such assessment is documented.
  3. If the patient exhibits signs or symptoms of OSA they must be referred for a medical assessment.
  4. Patients should be advised if appropriate of the risks and benefits of anti-snoring appliances, including any potential impact on the occlusion and the temporo-mandibular joints. Documentary evidence of the consent process must be kept.'

The dentist is often the key player in the treatment of snoring and apnoeas, and MAS therapy can be highly successful providing the appropriate appliance is selected.

The two principal factors to consider when treating such a patient are appliance retention and correct advancement. With a wide range of products on the market claiming to 'cure' snoring, it is important to prescribe with discrimination and select devices created and endorsed by a respected laboratory.