Purpose: This retrospective study evaluated the change in pharyngeal airway
space associated with surgical mandibular setback.
Patients and Methods: Lateral cephalograms of 14 adult patients taken preop
eratively, immediately postoperatively, and at longterm follow-up were trac
ed, and the width of the pharyngeal airway space and the pharyngeal airway
space area were calculated and compared.
Results: At long-term follow-up, the mean amount of mandibular setback was
9.7 mm. The mean reduction in the distance from the tongue base to the post
erior pharyngeal wall was 4.77 mm (28% decrease). The mean reduction in pha
ryngeal airway space area was 1.52 cm(2), which corresponded to a 12.8% red
uction. There was a strong correlation between the amount of mandibular set
back and the decrease in pharyngeal airway space area. Conclusion: Mandibul
ar setback surgery causes a long-term decrease in pharyngeal airway space a
rea. In patients who have other risk factors? for example, overweight, shor
t necks, or large tongues, a mandibular setback procedure could possibly pr
edispose to the development of sleep apnea syndrome.