PHARYNGEAL AIRWAY VOLUME FOLLOWING ...

employed to divide the airway into superior and inferior
components may not have been accurate since the maxillary
incisal edge most likely changed vertical position as a
result of surgery; therefore, the airway may not have been
separated at the same point along the posterior pharyngeal
wall. For future studies, a hard tissue landmark that is
not surgically altered could be utilized.
There are other variables that could have influenced
individual surgical results, including differential patient
response to surgery, soft tissue thickness, muscle
tonicity, body mass index, age, gender, and the fact that
both jaws were surgically repositioned rather than one jaw.
The results of the current study differ from other
studies that measured airway volume utilizing CBCT.
Stigall found no significant differences in airway volume
after mandibular advancement surgery. This may have been
due to the small sample size (n=9, 6 patients also had a
maxillary advancement surgery), soft tissue swelling of
tissues adjacent to the airway since post-surgical scans
were taken between 1 and 8 weeks post-surgery, and/or the
small amount of mandibular advancement (mean = 3.25 mm).
Sears 2 found a significant increase in airway volume
one month following surgery, but volume decreased at 6-8
months following surgery. Airway volume did not return to
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