COMPARISON OF CEPHALOMETRIC ANALYSIS WITH ETHNICITY IN OBSTRUCTIVE SLEEP-APNEA SYNDROME

Many studies have documented significant craniomandibular abnormalitie s in obstructive sleep apnea syndrome (OSAS) patients. Recent literatu re clearly describes the cephalometric abnormalities commonly associat ed with OSAS. Studies have not evaluated specific cephalometric abnorm alities that may contribute to OSAS by various ethnic groups. Data wer e collected on 48 patients (20 Caucasian, 15 Black and 13 Hispanic) wi th completed cephalometric analysis and polysomnography. Cephalometric landmarks, angles and measurements [angle measured from sella to nasi on to subspinale point (SNA), angle measured from sella to nasion to s upramentale point (SNB), difference between SNA and SNB (ANB), perpend icular distance from gonion to gnathion to hyoid (MP-H), distance from posterior nasal spine to tip of soft palate (PNS-P) and posterior air way space (PAS)] commonly used in the evaluation of OSAS patients were recorded. Measurements were normalized by dividing the observed value by the mean value for the ethnic group. Statistically significant dif ferences in normalized SNA and SNB appeared in the Black and Hispanic groups when compared to the Caucasian group. For both SNA and SNB, Bla cks averaged approximately 3.5% above their ethnic mean, whereas Hispa nics averaged 1.8-2.8% below their ethnic mean. There was a statistica lly significant correlation between respiratory distress index (RDI) a nd MP-H. These baseline cephalometric differences in the ethnic groups studied suggest that surgical intervention might be approached differ ently in various ethnic groups. Further studies that evaluate the surg ical success achieved by various procedures among different ethnic gro ups may help define surgical protocol in various ethnic groups for OSA S.