Can Oral Appliances Actually Open Your Airway? New Imaging Says Yes
If you’ve been diagnosed with obstructive sleep apnea (OSA), your doctor may have recommended a custom oral appliance as an alternative to CPAP. But many patients ask:
"Does it really do anything to the airway?"
A new study using 3D imaging (CBCT scans) confirms that oral appliances not only reduce apnea events — they also cause measurable, anatomical changes in the upper airway.
What Did the Study Look At?
Researchers used cone beam computed tomography (CBCT) to analyze pharyngeal airway dimensions in two groups:
20 adults with OSA who were treated with a custom mandibular advancement device (MAD)
20 matched control patients with OSA who received no treatment
Scans were taken with the patient in a supine (lying down) position, which simulates sleeping posture.
They measured:
Total airway volume
Minimum cross-sectional area (MCA)
Airway length and dimensions
Mandibular movement (jaw position)
What They Found
Oral appliance therapy significantly increased airway volume
Total pharyngeal airway volume increased by 26.1%
Minimum cross-sectional area improved by 42.8%
Posterior airway space enlarged significantly behind both the soft palate and tongue base
In the untreated group, no changes were observed.
This is one of the few real-world studies to confirm that oral appliances physically open the airway — not just reduce symptoms.
Why Does the Jaw Matter?
The oral appliances used in this study advanced the lower jaw (mandible) by 6.9 mm on average. This repositioning:
Pulls the tongue forward
Lifts soft tissues off the airway
Widens the airway behind the soft palate and tongue
These anatomical changes can reduce airway collapse, especially during REM sleep when muscle tone drops.
Why CBCT Imaging Matters
Traditional airway studies often rely on indirect measures — like symptoms, oxygen levels, or apnea events.
CBCT gives a direct 3D view of how the airway changes during treatment.
This is especially helpful for:
Educating patients
Personalizing appliance designs
Justifying treatment to insurance companies
What Does This Mean for Patients?
Oral appliances don’t just improve symptoms — they create real structural changes
If you’ve been hesitant about trying one, this study shows they’re backed by measurable results
For mild to moderate OSA — or for those who can’t tolerate CPAP — oral appliances are a proven, anatomical solution
TL;DR
Oral appliance therapy increased airway volume by 26% and minimum cross-sectional area by 43%
3D scans showed widening of the airway behind the tongue and soft palate
These anatomical changes help prevent airway collapse during sleep
Oral appliances are not just symptom relievers — they create real physical improvements
Source:
Cao Y, Zhang X, Li Z, et al. Comparison of Pharyngeal Airway Changes in Patients with OSA Treated with Oral Appliances Versus Untreated Controls: A CBCT Study. American Journal of Orthodontics and Dentofacial Orthopedics. 2023;163(3):e249–e258.
https://doi.org/10.1016/j.ajodo.2022.09.015