Obstructive Sleep Apnea (OSA)

Obstructive Sleep Apnea - What it is

Obstructive sleep apnea (OSA) is a condition whereby a person experiences repeated blockage to breathing during sleep. The airway collapses or becomes blocked and this can severely affect the quality of sleep.

Given the possible long term complications of obstructive sleep apnea, it is important for patients to follow-up with appropriate treatment once diagnosed. The management of obstructive sleep apnea is multidisciplinary in nature, and may involve specialists from dental specialities such including oral and maxillofacial surgery and orthodontics, and medical specialties such as otolaryngology.

Treatment for obstructive sleep apnea range from non-surgical options to surgical options.

Obstructive Sleep Apnea - Symptoms

One of the most common sign of Obstructive sleep apnea (OSA) is snoring or gasping for air during sleep. As the quality of sleep is affected, you may experience day time sleepiness while working or driving.

Other symptoms include:

Morning headaches
Dry mouth
Sore throat
Feeling of tiredness after a night’s rest

Obstructive Sleep Apnea - Causes and Risk Factors

Obstructive sleep apnea occurs when the throat muscles and tongue are more relaxed during sleep resulting in a collapse of the airway. An enlarged tongue or tonsils will also cause obstruction or narrowing of the airway.

Being overweight can also be a causative factor as the excess fatty tissue in the airway can narrow the windpipe.

Untreated obstructive sleep apnea can pose a possible risk for heart diseases such as high blood pressure, heart attack or stroke. Other risk factors include obesity and diabetes.

Obstructive Sleep Apnea - Diagnosis

Diagnosis is based on a thorough sleep history, a physical examination and sleep study. A good history consists of sleep patterns and presence of any snoring or day time sleepiness.

This will be followed by an examination of the airway via an endoscope to assess for any narrowing of the airway.

Your physician may send you for a sleep study which is the gold standard for diagnosing Obstructive sleep apnea (OSA).

Obstructive Sleep Apnea - Treatments

Non-Surgical Options

1. Oral Appliances

Mandibular Advancement Splints are oral appliances that are fitted on the upper and lower teeth, and works by posturing the lower jaw forward, thereby opening up and maintaining the upper airway during sleep. These devices are potentially effective in patients diagnosed with mild to moderate OSA (see section on 'Diagnosis'), particularly where the airway obstruction occurs at the level of the tongue. Adjustments may be necessary in the first few months.

An adjustable oral appliance with connectors at the side, A Tap-T oral appliance with a connector in front, by NDCS

Mandibular Advancement Splints: What To Expect

In the first few weeks, you will find the splint very uncomfortable. Your lower jaw is held forward during the night and you will experience aching of the jaw muscle in the first few hours of the morning. You will also feel as though your teeth do not fit together properly. These symptoms usually disappear by noon.

You will experience a lot of saliva and drooling in the first few weeks of wearing the splint. You may want to sleep with a handkerchief or towel on your pillowcase. Sometimes, you will wake up to find that you have unknowingly removed the splint during sleep.

The initial problems will gradually go away after a while. To make it easier for you to get used to the splint, put it on 1 to 2 hours before you go to sleep.

In more cases, snoring will be reduced to an acceptable level or it will disappear. The number of apnoeas or cessations of breaths per hour will be reduced to a less harmful level.

The application may take several weeks to become effective, as the tissues of the airway may have been damaged from prolonged snoring. If you have daytime sleepiness, it takes a few weeks before you notice the difference and begin to feel good.

After you have used the splint for some time, you can sleep without it for 1 to 2 nights a week and the positive effects continue to stay with you.

Mandibular Advancement Splints: Adverse Effects

Your jaw-joints and your teeth support the forward position of your lower jaw. If you have had joint problems with clicking and pain before, these problems can return and your splint will have to be altered. If you have a new filling or crown made, alterations of the splint is necessary.

If you have gum disease, support for your teeth is not as strong and your teeth can shift. It is important to make regular visits to your dentist in order to keep your gums healthy and to prevent cavities from developing in your teeth.

Long term wear of the splint may alter the way your teeth meet. The over jet and overbite of your front teeth will be reduced. There will be a mild increase of the lower face height.

The side effects are minor and outweigh the effects of the splint.

2. Continuous Positive Airway Pressure (CPAP)

A CPAP machine consists of a pump that generates airflow, a tube that carries airflow to the patient, and a mask that covers the nose, mouth or both. By generating a constant positive airway pressure, CPAP machines maintain the patency of your airway during sleep.

Surgical Options

Surgery is sometimes recommended for severe cases of Obstructive sleep apnea (OSA). It is the next option for patients with moderate to severe OSA who turned down CPAP therapy after finding it difficult to use the CPAP machine. Patients must be medically fit to undergo surgery.

All cases for surgery are examined thoroughly in order to customise the treatment plan. Soft and hard tissue surgery are planned to cater to the needs of each patient. In many instances, the multidisciplinary approach is taken and a team of surgeons is brought in for combined surgery. Sometimes, it may be necessary to stage surgical treatment into separate surgeries done at different times.

Oral and maxillofacial surgeons carry out jaw surgery. The otolaryngology (ear, nose and throat) surgeons carry out surgeries to the nose, palate and throat.

Types Of Hard Tissue Surgery

Genioglossus Advancement Surgery is surgery of the chin. This pulls the tongue muscle forward and creates a larger airway between the back of the tongue and the throat. The tongue is also less likely to fall backwards, resulting in easier breathing during sleep.

Difference in airways after Genioglossus Advancement Surgery, National Dental Centre Singapore

Maxillomandibular Advancement (MMA) is a more invasive surgical procedure that brings forward both the upper and lower jaws. This pulls on the soft tissues attached to the jaw bones, tightening up the lax tissue at the back of the nose, mouth and voice box. The airway also becomes bigger. The procedure is done using well-established orthognathic (jaw) surgery techniques. Long-term studies have shown a 90% success rate with this procedure.