Validation of a Simplified MATRx Plus Theragnostic Sleep Study

Sleep apnea (OSA) is a condition in which the air passage in the throat closes or partly closes during sleep and repeatedly interrupts breathing. The standard treatment for sleep apnea is continuous positive airway pressure (CPAP), but it is not suitable for all patients. Another treatment is to use an oral appliance in your mouth when you sleep. The appliance covers the upper and lower teeth and acts to pull the lower jaw forward, opening the throat passage and allowing normal breathing.

Oral appliance therapy does not treat sleep apnea effectively in everyone. In order to identify the people in whom oral appliance therapy will work, Zephyr Sleep Technologies has invented a feedback-controlled device that tests various positions of the lower jaw. This commercially available device, known as MATRx plus, is a Health Canada approved and FDA cleared motorized dental positioner that can be used in an overnight sleep study performed in the home. Temporary dental impression trays cover your upper and lower teeth. These are attached to a small motor that slowly and gently pulls your lower jaw forward under the control of a computer in response to real-time breathing events. The commercial MATRx plus device uses measures of airflow from a nasal cannula and blood oxygen saturation from a pulse oximeter to guide the movement of the lower jaw during the test. Though the test is accurate, the equipment can be somewhat cumbersome to apply. The purpose of the study is to validate a simplified version of the test that requires fewer sensors and sleep time.

We have previously carried out three research studies leading to the development of the feedback-controlled mandibular positioner. These studies, two of which used early prototypes of the device and one that used the commercial MATRx plus device, showed that the feedback-control software used was very accurate and was able to identify successful candidates in a home setting.

No serious or permanent problems or risks were identified in any of the previous research studies. Participants reported minor tooth and gum discomfort on the morning following the test and other minor issues including dry mouth, excessive saliva, and being unable to sleep. The previous studies have established the safety and efficacy of the device using a device prototype. The purpose of the present study is to determine if the efficacy of the device is maintained when fewer sensors are used and the requirement for sleep time is reduced.

The study will collect data over one night in a sleep laboratory and a series of nights in the home. Following the study, you will be told if you are a suitable candidate for oral appliance therapy. If you do not already have a custom oral appliance, one will be provided to you. During the study, the Principal Investigator and study dentist will be blinded to the results of your tests. In the event of an emergency, the Principal Investigator can be unblinded to your test results.