“The problem with MADs is that the dentist doesn’t always know who will respond to MADs or exactly how much protrusion is needed for effective therapy,” Dr. Remmers said. He added that the adjustments or titrations that are done to get a positive response are often highly subjective and rely less on precision than guesswork. “This all leads to the difficulty for the physician in both selecting patients for MADs and providing a recommendation on how much to adjust the oral appliance to achieve efficacy,” he said.
Explore this issue:December 2011
Tongue-stabilizing devices (TSDs) are not as well studied or used. However, results of a recent randomized study that compared TSDs to MAS (mandibular advancement splint) suggest that MAS may remain the preferred device for now based on lower tolerance associated with TSDs despite comparable efficacy (Sleep. 2009;32(5):648-653).
“In clinical practice, the use of MAS is likely to predominate,” said Peter Cistulli, MD, head of sleep medicine at the University of Sydney’s Sydney Medical School in Australia. He added, however, that the development of more tolerable methods of advancing the tongue may be warranted given a recent study he and his colleagues conducted that found that the magnitude of upper airway enlargement was greater with TSD than with MAS (Sleep. 2011;34(4):469-477).
Efficacy of MADs
Several studies have shown the efficacy of MADs for improving snoring, reducing excessive daytime sleepiness, effecting some improvements in neuropsychological functioning and modestly reducing blood pressure in patients with OSA (Curr Opin Pulm Med. 2009;16(6):591-596). Most data show that the effect of these devices on AHI and oxygen saturation is lower than the effect seen with CPAP, but the better compliance seen with oral devices may result in comparable outcomes between these two modes of treatment.
Dr. Lowe emphasized the importance of educating otolaryngologists about the usefulness of oral appliances and their feasibility as another adjunct to OSA treatment. “The advantage of an oral appliance is that it is worn more but may be less effective for oxygenation. The advantage of CPAP is that it is worn less but is more effective for oxygenation,” he said. “What really matters is how the quality of life for the patient has changed, and this outcome is pretty comparable between oral devices and CPAP.”
One overall limitation of the studies on MADs to date has been the quality of the evidence used to make treatment decisions, which, according to a 2011 review of the literature commissioned by the Agency for Healthcare Research and Quality (AHRQ), is only moderate to insufficient (AHRQ Comparative Effectiveness Reviews. 2011;32).