Maxillomandibular advancement (MMA), a surgical procedure that moves both the upper and/or lower mandibles forward, can yield a noticeable improvement in patients with obstructive sleep apnea (OSA), according to a study in the Journal of Oral and Maxillofacial Surgery (August 2013, Vol. 71:8, pp. 1397-1405).
The study is significant to patients with the dangerous and often life-threatening signs of airway obstruction during sleep, according to the American Association of Oral and Maxillofacial Surgeons.
To evaluate the outcomes of MMA for patients with OSA, researchers at the University of Alabama at Birmingham studied eight patients diagnosed with mild to severe OSA who had undergone maxillomandibular advancement surgery. All study participants underwent pre- and postoperative CT scans to establish upper airway CT datasets with 3D models to study how the surgical changes in airway structure affected the pressure effort required for normal breathing.
By comparing the pre- and postoperative airway dimensions, skeletal changes, apnea-hypopnea index, and pressure effort of the 3D models, the researchers were able to interpret the surgical results. Significantly, they found that by surgically increasing the distance from the occipital base, or back of the skull, to the pogonion, or forward point on the chin, MMA significantly increased patients' airway dimensions.
This increase reflects an improvement in the apnea-hypopnea index used to gauge the severity of OSA and a decreased pressure effort of the upper airway, a factor that decreases the patient's needed effort to breathe, the researchers noted.
