title: Craniofacial shape in children with and without a positive otitis media history.
abstract: OBJECTIVE
  Past studies using traditional morphometric approaches have reported a handful of differences in craniofacial dimensions between individuals with and without otitis media (OM). In this study, a geometric morphometry (GM) approach was used to determine if craniofacial shape is different among children with no history of OM and a history of recurrent acute OM (RAOM) at two different ages.
  
  
  METHODS
  Nineteen standard landmarks were identified on lateral cephalometric radiographs from 79 children (41 Control, 38 RAOM) at 4 years and 52 children (27 Control, 25 RAOM) at 6 years of age. Following Procrustes superimposition of the landmark coordinate data, comparisons of group differences in overall size and shape were performed. Discriminant function analysis and principal component analysis were used to determine which, if any, aspects of shape variation distinguished RAOM from Control groups.
  
  
  RESULTS
  At 4 years of age, craniofacial size and shape were significantly different between RAOM and Control groups (p<0.05). Shape differences were evident in the relative positions of the mandible, cranial base, external acoustic meatus, sphenoid and palate. Those shape differences were not found in the 6-year old group.
  
  
  CONCLUSIONS
  At 4 years of age, the RAOM and Control groups have distinct craniofacial morphologies, but by 6 years of age these differences have largely disappeared. This is consistent with the clinical observation that excess RAOM risk resolves around 6 years of age and the hypothesis that this resolution is partially a result of age-related craniofacial changes.
authors.affiliation: Department of Anthropology, University of Pittsburgh Dietrich School of Arts and Sciences, United States. Electronic address: apc22@pitt.edu.
authors.forename: Allison P
authors.initials: AP
authors.lastname: Gremba
authors.affiliation: Center for Craniofacial and Dental Genetics, Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, United States.
authors.forename: Seth M
authors.initials: SM
authors.lastname: Weinberg
authors.affiliation: Department of Otolaryngology, University of Pittsburgh School of Medicine, United States.
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Swarts
authors.affiliation: Department of Otolaryngology, University of Pittsburgh School of Medicine, United States.
authors.forename: Margaretha L
authors.initials: ML
authors.lastname: Casselbrant
mesh_terms: D000208:Acute Disease; D000367:Age Factors; D016022:Case-Control Studies; D002508:Cephalometry; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010033:Otitis Media / Q000209:etiology*; D025341:Principal Component Analysis; D012008:Recurrence; D012886:Skull / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000254:growth & development
keywords: Children; Craniofacial shape; Geometric morphometrics; Otitis media