The team tested a titratable device that identified responders and non-responders during DISE.

By Sree Roy

Anticipating the effects of an oral appliance on the upper airway during similar conditions to sleep would provide invaluable information for patients with sleep-disordered breathing who fail or refuse CPAP.

While some sleep medicine teams opt for drug-induced sleep endoscopy (DISE) to predict therapeutic impact, Patricia Fernández-Sanjuán, DDS, and a team of co-investigators in Madrid, Spain, saw evidence that the common manual protrusion maneuver done during DISE is lacking in predictive value and that trying bite registrations with different advancement measurements may provoke arousal during the procedure.

So they designed a titratable device called SAM [Selector Avance Mandibular], adapted individually to the patients’ maxillary and mandibular arches, to be used during DISE. Fernández-Sanjuán says, “The protrusive range of each individual is determined to assess their tolerance and to not to exceed it while under sedation. This manually controlled device allows pulling the jaw during sedation. We are able to see millimeter by millimeter the changes that the mandibular advancement may or may not cause in the stabilization of the upper airway. The mandibular positions that we want to analyze can be fixed for the necessary time both in supine and lateral head/trunk rotation.

“With the SAM we imitate in a simple, reproducible, and personalized way the mandibular advancement. This device helps us to identify the minimum effective advancement for each individual. Also, we are able to reach the maximum tolerable advancement to analyze if the collapsibility increases with titration—since reduction in apnea-hypopnea index is not always dose dependent. In summary, it helps to optimize the test procedure by reducing the patient arousal and reducing exploration time, while also allowing exploration of the upper airway behavior introducing mandibular advancements from zero to maximum protrusion without removing the device from the mouth. “

The DISE procedure with SAM was able to predict responders and non-responders to mandibular advancement. The American Academy of Dental Sleep Medicine (AADSM) awarded the resulting abstract a Clinical Research Award for 2020 and published it in the April 2020 edition of the Journal of Dental Sleep Medicine.

The study used evaluated changes in volume and collapsibility of the upper airway at the level of the velopharyxn, oropharynx, base of tongue, and epiglottis. “According to our results, upper airway in patients with primary snoring showed more changes in velopharinx and oropharinx with the SAM,” says Fernández-Sanjuán. “In patients with mild [obstructive sleep apnea] changes occurred at a higher level, ie, the biggest change was shown at velopharynx, followed by the orapharinx and the base of the tongue level. The epiglottis level did not show a significant change. For moderate patients, all four studied levels showed significant differences, but the velopharynx and tongue levels presented the largest changes. Conversely, in severe patients, the mandibular advancement produced significant changes, which were similar across all levels (velopharynx, oropharynx, base of the tongue, and epiglottis levels).

“These results demonstrate that in mild cases of OSAS, the mandibular advancement helps to reduce the collapsibility of the upper airway at higher levels. Whereas, in more severe cases, where usually a multilevel collapse occurs, the mandibular advancement contributes to prevent in responders the collapsibility at all levels, particularly at the base of the tongue.”

Fernández-Sanjuán says that the study’s results may be most relevant for patients with moderate or severe sleep-disordered breathing who are looking for alternatives to CPAP. “One of the indications for oral appliance therapy is in severe obstructive sleep apnea syndrome (OSAS) patients who refuse or prefer an alternative to CPAP. However, according to our results, approximately 70% of severe OSAS patients would not respond to an oral appliance. But also, in 40.5% of the severe OSAS patients, a combination therapy was proposed (especially oral appliance therapy combined with surgical procedures, which were decided after the information obtained from this test).”

Sree Roy is editor of Sleep Review.


Fernández-Sanjuán P, Sanabria J, Moreno-Hay I, et al. Use of mandibular positioning device during drug induced sleep endoscopy for patient selection in oral appliance therapy: observational multicenter study in patients with primary snoring and obstructive sleep apnea. JDSM. 10 Apr 2020;7.2:Abstract #013.