THE WEBSITE OF ALLEN J. MOSES, DDS
SEARS TOWER - CHICAGO
ORAL APPLIANCES FOR TREATING
OBSTRUCTIVE SLEEP APNEA
Decisions on treatment are customized for each patient based on the medical history, sleep specialist's examination, results of the sleep lab study, the individual's unique needs, preferences, health problems and life style. Success of the selected treatment can and should be verified by a repeat study in the sleep lab.
Oral Appliances for the treatment of apnea, hypopnea and snoring are fabricated and fitted by dentists. There are two main categories of oral appliances - Tongue Retaining Devices (TRDs) and Mandibular Advancement Devices (MADs). Both result in the tongue being in a more forward position than normal and the mouth being held open beyond its normal rest position. They presumably keep the airway open by preventing collapse of the tongue on the soft palate and throat.
TRDs utilize the suction generated into a rubber bulb to actively pull and hold the tongue into a forward position protruding beyond the incisor teeth. The lower jaw, which is attached to the tongue, is passively pulled forward. Because the mouth must be sealed around the TRD to sustain the necessary suction, its use is absolutely contraindicated in patients who are mouth breathers. A patent nasal airway is a cardinal principle in prescribing a TRD.
MADs are fabricated over the teeth so the lower jaw is held more open and protrusive than in the normal biting position. In the MAD the mandible is actively pulled forward and the anterior repositioning of the tongue is passive. Scientific studies have demonstrated that MADs dilate pharyngeal muscles, thus helping prevent collapse of a drooping soft palate. The modified jaw position in a MAD raises the hyoid bone relative to cranial base and extends the neck to a position similar to the one in which CPR is initiated, thus helping maintain an open airway. MADs lower elevator muscle activity, reducing clenching and preventing bruxism. They increase volume of space for the tongue in the mouth. Further, some MADs correct dysfunctional swallowing and some have been shown to increase nasal airflow.
Both MADs and TRDs have advantages and disadvantages. At the present time there are over fifty different mandibular advancement devices available for dentists to choose from. No one yet is the perfect device. MADs are generally more comfortable and better tolerated by most patients than TRDs. MADs can be made for patients with nasally compromised breathing. The overwhelming majority of oral appliances currently being prescribed for apnea and snoring are MADs.
Whichever oral appliance is prescribed for OSA and snoring, as with all other alternative treatment regimens, there is no guarantee of success. Various home monitors are available to objectively evaluate progress each time the device is adjusted. After the dentist has adjusted the oral appliance to maximum performance a final study should be done in the sleep lab to confirm results. The gold standard is still polysomnography.
Oral appliances are not always as effective as CPAP. The importance of titration adds to the cost. Because it is time consuming for the dentist to repeatedly adjust and then measure outcome each time, their cost may be higher than CPAP.
There are side effects to the use of oral appliances. There is an initial accommodation period of getting used to sleeping with a foreign device in the mouth. Symptoms such as tooth discomfort and excessive salivation are common. In the morning when the appliance is removed, there is often a period of 15 - 45 minutes necessary for the jaw to reprogram itself from the forward bite to the habitual bite. Occasionally, there is some tooth movement and bite change as a side effect. Rarely are they serious enough to discontinue using the appliance, but regular, semi-annual check-up visits to the dentist are important.
One problem with oral appliances is that dental work done after fitting and adjustment has been completed may seriously compromise fit and function. Major dental work done subsequent to fitting the appliance could necessitate a remake. Any anticipated dental work should be done before fabrication of an oral appliance for snoring and/or apnea.