Trial on Oral Appliance Design for Improving Upper Airway Function and Sleep Quality

Mid-line Traction Versus Bilateral Thrust Oral Appliances: A Trial to Determine Superiority for Improving Upper Airway Function and Sleep Quality

This study will compare the effectiveness of the two leading oral appliances (OAs) designs for the treatment of severe obstructive sleep apnea in overweight adults. The effectiveness of OAs has come under question since different designs are combined in evaluating treatment efficacy, for example when comparing them to continuous positive airway pressure Due to the wide range of reported efficacy (53 to 90%), it is of great value to identify the most effective design to guide sleep practitioners and patients.

The two prominent oral appliances used in treating obstructive sleep apnea differ in their designs, mid-line traction versus bilateral thrust. From a clinical perspective, it is important to know which design is superior and should be the 'treatment of choice' for improving airway function and sleep quality. These two designs differ in their protrusive mechanisms that are categorized in general under four main types: bilateral compression, bilateral thrust, midline compression and mid-line traction. Although the two designs considered in this proposal have undergone the most rigorous testing individually, well controlled 'head-to-head' trials as proposed here have not been conducted to determine their efficacy within a single test population.

Inclusion Criteria:

• OSA PSG or PG diagnosed adults within 1 year
• age >18
• Currently treated with continuous positive airway pressure (CPAP)
• AHI ≥ >30 events/hour of sleep
• Two or more OSA symptoms (snoring, witnessed apnea or daytime hypersomnolence complaint)
• BMI ≥ 30
• At least 8 teeth per arch to support either OA device
• Central and mixed apnea index <5 events/hour
• Mallampati score from I to III
• Palatine tonsils - grade 0, 1, or 2
• Consent to study's timeline
• Willingness to wear home sleep test apparatus for at least 4 nights
• Willingness to wear an oral appliance every night for 8 weeks
• Willingness to pick up and return home sleep test kits as needed

Exclusion Criteria:

• Cardiac & pulmonary disease (e.g., congestive heart failure, severe arrhythmias, COPD);
• Central sleep apnea;
• Comorbidities with other sleep disorders
• No active TMD or jaw muscle pain
• Morphological airway abnormalities
• Pre-existing difficulty swallowing; throat or neck related health issues
• Endocrine dysfunction
• Severe psychiatric disorders;
• Previous OA therapy; ENT surgery
• Restrictions in jaw opening
• Pregnancy / breast feeding or intent to become pregnant during the study
• Inability to apply the sleep recorders