Treatment – Oral Appliance Therapy
The goal of Oral Appliance Therapy (OAT) is to open the airway. Oral appliances fall into two basic categories: tongue-retaining devices (TRD) and mandibular advancing devices (MAD). Tongue-retaining devices are small acrylic devices which fit by suction on the tip of the tongue. Mandibular advancing devices are small acrylic devices that fit over your upper and lower teeth and advance the lower jaw. Both move the base of the tongue forward and open the airway. TRDs do not work as well as MADs. They are non-invasive, easy to use and are effective in improving breathing, reducing snoring and reducing mild sleep apnea. They are less effective for treating people with moderate or severe obstructive sleep apnea and people who are obese. Sleep appliances offer several advantages over other therapy. They are not as expensive, easy to travel with, non-invasive, easy to fabricate, and quite well accepted by patients.
Guidelines from the American Academy of Sleep Medicine
Oral appliances are indicated for use in patients with mild to moderate sleep apnea who prefer them to CPAP therapy, patients who do not respond to CPAP and patients who are not appropriate candidates for CPAP or fail CPAP treatment attempts.
FIRST Line Treatment
(a) Mild to moderate Obstructive Sleep Apnea Syndrome ( AHI 5-30 ) for patients who:
- Prefer MRDs over CPAP
- Do not respond to CPAP
- Are inappropriate candidates or fail CPAP
- Fail behavioural measures treatment
(b) Primary snoring for patients who do not respond or are not appropriate candidates for behavioural measures treatment
SECOND Line Treatment
(a) Severe Obstructive Sleep Apnea Syndrome ( AHI greater than 30 ) in case of lack of compliance with CPAP
Oral appliances have a definite role in the management of selected patients with sleep apnea and/or snoring. The appliance will not cure the apnea and/or snoring but works non-surgically to realign the jaw and/or tongue to keep the airway open. Its intention is to prevent the apnea and/or snoring from occuring during sleep and so it must be worn each night to produce the desired effect. Regardless of how long it is worn, the symptoms of obstructive sleep apnea or snoring will return when the appliance use is discontinued. There are no guarantees that an appliance will be successful in every patient due to physiologic and anatomic variations and patient tolerance of the appliance.
Oral appliances that treat snoring and obstructive sleep apnea are devices worn in the mouth, similar to orthodontic retainers or sports mouthguards. They have several advantages over other forms of therapy. Oral appliances are comfortable, easy to wear and care for, and non-invasive. They are small and convenient, making them easy to carry with you when you travel.
Oral appliance therapy is becoming recognized by the medical community as an effective treatment option in the management of sleep breathing disorders. Medical and dental researchers have joined together to evaluate and improve the outcome of treatment with oral appliances. The American Academy of Sleep Medicine recommends oral appliances be used in patients with primary snoring or mild obstructive sleep apnea and in patients with moderate to severe obstructive sleep apnea who are intolerant of or refuse treatment with nasal continuous positive airway pressure.
Research shows that oral appliance therapy is 85%-90% effective in reducing or eliminating snoring and 60%-70% in reducing mild-to-moderate sleep apnea to normal.
Oral appliances may be used alone or in combination with other means of treating obstructive sleep apnea, including general health and weight management, surgery or nasal continuous positive air pressure (CPAP). Combination therapy should be coordinated by the attending sleep physician.
Oral appliances work in several ways:
- by repositioning the lower jaw and/or tongue
- by stabilizing the lower jaw and tongue
- by increasing the tone of the throat muscles
Oral appliance therapy can take from several weeks to several months to complete. Even after the initial phase of treatment is complete, follow-up visits should continue in order to ensure treatment remains successful and to evaluate the response of the teeth and jaws.
There are two basic categories of oral appliances: tongue-retaining devices and mandibular advancing devices.
Tongue Retaining Devices (TRD)
Tongue Retaining Devices (TRD) are custom-made appliances with an anterior bulb that holds the tongue in a forward position during sleep by means of negative pressure (or suction). Currently, the TRD appears to be the appliance of choice for patients who have few or no teeth and for patients who have large tongues. In addition, the TRD is a good appliance for patients who cannot adequately advance their mandible for whatever reason. Its disadvantages are that it is more difficult for both clinicians and patients to use on a regular basis, it poses problems for patients who cannot breathe through their nose, it irritates the end of the tongue over time and it is a single jaw and tongue position appliance.
Mandibular Advancing Devices (MAD)
These devices fit over both the upper and lower teeth and move the lower jaw forward, which brings the tongue and some throat tissues along with it, opening the airway. They also stimulate the pharyngeal muscles to maintain an open airway during REM sleepthe muscles that normally relax during REM sleep. There are several different designs for Mandibular Advancing Devices. Some designs are not adjustable after fabrication and have to be remade if any alterations are required. Others have an excellent range of adjustment. MAD appliances, in general, require a healthy jaw joint and several healthy teeth with healthy gums in both the upper and lower jaw.
Some of the common side effects with the use of oral appliances are excessive salivation, discomfort in the teeth, dry mouth, tissue irritation from mouth breathing, temporary disharmonies in the bite and some pain in the joint. These side effects are usually short-lived. Upon occasion a poorly fitting crown or filling may be dislodged.
With all long term appliance therapy there will be some tooth movement; some favourable and some unfavourable. Discuss this very real possibility with your dentist.
Boil and Bite Appliances
These appliances are prefabricated oral appliances lined with a soft, thermoplastic material that is moulded to the patients teeth in the dentists office. It engages the mandible mainly at the incisors; therefore, it applies the force of advancement to fewer teeth than appliances that utilize coverage of all teeth. The advantages are its relatively low cost and fewer appointments. The disadvantages are it may apply excessive pressure to the lower anterior teeth in some patients and problems with the fit of the appliance may develop over time. Also, it is not as adjustable or durable as a laboratory-fabricated appliance and thus the low initial cost is not as attractive over the long term.
Laboratory fabricated appliances require the attending dentist to take mouth impressions which are used to make models of the teeth and gums. These are then used by the laboratory to make the appliance. They are generally more durable, better fitting, and more expensive. There are several kinds of laboratory-fabricated devices. Two excellent examples are the Klearway appliance and the Thornton Adjustable Positioner (TAP) appliance.