Obstructive sleep apnoea (OSA)

What causes snoring and sleep apnoea?

The most common OSA predisposing factors are shown below:

  • Overweight
  • Nasal stuffiness
  • Late evening alcohol
  • Use of night time sedatives
  • Residual tonsils
  • Smoking
  • Receding lower jaw
  • Hypothyroidism
  • Menopause
  • Sleeping on your back

If one or more of these factors are present, you may find that you can successfully help yourself or your bed partner with simple lifestyle modifications. However, sometimes none of the potential causes can be identified and/or no beneficial effect is seen after the OSA predisposing factors have been addressed.

What has the dentist to offer snorers?

There is good evidence that custom made intra-oral appliances – mandibular repositioning appliances (MRAs) [variously known as MRDs – D for device] worn in the mouth at night can greatly help reduce snoring. They work by holding the lower jaw and tongue forward during sleep. The narrowing of the airway behind the tongue is prevented thus reducing the likelihood of snoring and even apnoeic episodes.

MRDs are primarily indicated for the treatment of simple, non apnoeic snoring as well as for mild – moderate OSA when prescribed and monitored as part of a multidisciplinary team.

If you or your bed partner has any of the symptoms of obstructive sleep apnoea listed above you will be referred to a specialist sleep physician for specialist investigation and diagnosis before treatment is started.

MRDs consist of close fitting, custom made ‘rims’ that fit around the upper and lower teeth. These rims are connected in various ways to allow the lower jaw to be postured and held in a forward position. Many of these appliances will allow some horizontal and vertical lower jaw movement.

MRDs impose significant forces to the teeth and jaw joints and the dentist has to be satisfied that these structures are sound and able to withstand these forces. Side effects of treatment may include excess salivation (sometimes a dry mouth), jaw joint ache and tooth sensitivity. These are short-term side effects and usually disappear once you become accustomed to the appliance. Evidence of long-term side effects include minor tooth movements and bite changes. These side effects must be balanced against the benefits of treatment. Most patients do not find these side effects sufficiently intrusive to discontinue treatment.

Modern, custom-made appliances are sophisticated and comfortable to wear. The images below have been kindly supplied by their respective manufacturers. The BSDSM does not endorse any particular one.

What has surgery to offer for snorers?

If MRD therapy has failed then surgery may be an option.

Nasal stuffiness (the inability to breath easily through your nose) may sometimes be treated by surgery. Sometimes it may worth removing residual tonsils, although in adults this is not a trivial operation.

If appropriate, throat and soft palate surgery may be considered. Surgical removal of part of the soft palate and uvula – uvulopalatopharyngoplasty or UPPP was commonly performed but was associated with serious side effects such as; severe post operative pain, difficulty in swallowing and voice changes. As a result of high relapse rates, this operation is no longer routinely prescribed.

Other surgical operations on the palate, such as laser scarring,  or radio-frequency ablation do not appear very successful.

Exceptionally, surgery to enhance the performance of CPAP or an Oral Appliance may be recommended.

Treatment of Sleep Apnoea

CPAP (continuous positive airway pressure) is considered the first line of treatment for severe OSA and is very effective in terms of overcoming the symptoms of excessive daytime sleepiness. Patients with severe sleep apnoea respond well to this therapy. However, it is without doubt an arduous therapy, which involves wearing a mask during sleep (over the nose or nose and mouth), which is connected to a small air pump. The treatment works by blowing air into and pneumatically inflating the collapsible part of the upper airway, thus preventing vibration and blockage of the flexible upper airway breathing tube. Subsequently, sleep apnoea and snoring are prevented.

If your medical history and screening suggests there is a likelihood that you are suffering from OSA then you will be referred to a Respiratory Physician for a sleep study and diagnosis. This may involve spending a night at a hospital ‘Sleep Laboratory’ or more usually, you will be given a portable monitor so that a simpler study can be carried out in the comfort of your own home. Such monitors can record your heart rate, your blood oxygen carriage, your breathing (including any apnoeic events), snoring events and body position.

Once diagnosed by the Consultant Respiratory Physician, custom MRD therapy may be prescribed. The exact therapy depends upon the severity of your sleep apnoea and the existence of other medical problems. Oral appliances can be used to treat all severities of sleep apnoea but effective results are less certain with increasing severity of apnoea. Severe sleep apnoea, if treated with an oral appliance, requires careful patient monitoring.

Such custom made oral appliances can only be made, fitted and monitored by trained dentists.

When MRDs are used as an alternative treatment for severe OSA the trained dentist MUST be working as part of a multidisciplinary team, which would include either a Consultant ENT surgeon or Respiratory Physician.