title: Maxillary morphology in obstructive sleep apnoea syndrome.
abstract: The aim of this case-control study was to test the hypothesis that maxillary morphology differs between obstructive sleep apnoea (OSA) patients and non-snoring, non-apnoeic subjects. Forty randomly selected patients [36 M, 4 F; mean age 49 +/- 2 (SEM) years] with varying degrees of OSA (mean Apnoea/Hypopnoea Index 32 +/- 4/hour) were compared with 21 non-snoring, non-apnoeic control subjects (18 M, 3 F; mean age 40 +/- 2 years). An intra-oral assessment of the occlusion was carried out, particularly for the presence or absence of posterior transverse discrepancies. Maxillary dental arch width was assessed by standardized lateral inter-tooth measurements (inter-canine, inter-premolar, and inter-molar) from dental models. Palatal height and maxillary depth were also measured. The maxillary dental arch was described by a 4th order polynomial equation. The ratios of maxillary to mandibular width (max/mand) and maxillary to facial width (max/facial) were determined from standardized postero-anterior cephalometric radiographs in a subgroup of patients (n = 29) and all controls. Twenty patients (50 per cent) had evidence of posterior transverse discrepancies compared with one control subject (5 per cent; P < 0.01). All patients had significantly reduced inter-canine, inter-premolar, and inter-molar distances (P < 0.05). The maxillary depth was also shorter (P < 0.05), but palatal height was not different. The quadratic coefficient of the polynomial equation was greater in the patients than in the controls (P < 0.05), indicative of greater arch tapering. Patients had smaller maxillary to mandibular and maxillary to facial width ratios (P < 0.01). These results suggest that OSA patients have narrower, more tapered, and shorter maxillary arches than non-snoring, non-apnoeic controls. Further work is required to determine the relevance of these findings in the pathophysiology of OSA.
authors.affiliation: Centre for Sleep Disorders & Respiratory Failure, St George Hospital, University of New South Wales, Australia.
authors.forename: B H
authors.initials: BH
authors.lastname: Seto
authors.forename: H
authors.initials: H
authors.lastname: Gotsopoulos
authors.forename: M R
authors.initials: MR
authors.lastname: Sims
authors.forename: P A
authors.initials: PA
authors.lastname: Cistulli
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002508:Cephalometry; D016009:Chi-Square Distribution; D003724:Dental Arch / Q000473:pathology; D003817:Dentition; D005260:Female; D006801:Humans; D008297:Male; D008437:Maxilla / Q000473:pathology*; D008875:Middle Aged; D008954:Models, Biological; D010100:Oxygen / Q000097:blood; D020181:Sleep Apnea, Obstructive / Q000473:pathology*; D018709:Statistics, Nonparametric; D013577:Syndrome
chemical_list: D010100:Oxygen