title: Cephalometrics in Stickler syndrome: Objectification of the typical facial appearance.
abstract: BACKGROUND
  Stickler syndrome is a connective tissue disorder characterized by orofacial, ocular, skeletal and auditory symptoms. The orofacial phenotype mainly consists of midfacial hypoplasia, micrognathia and cleft palate. Large phenotypic variability is evident though. Few studies have tried to substantiate the typical facial appearance in Stickler syndrome patients.
  
  
  METHODS
  Molecularly confirmed Stickler patients were invited to undergo cephalometric analysis based on a lateral radiograph in standardized conditions. Angular and linear measurements were performed according to Steiner's and Sassouni's analysis and compared with age- and gender-matched reference values.
  
  
  RESULTS
  Thirteen patients aged 10-62y were included, twelve of whom had type 1 Stickler syndrome (COL2A1 mutation) and one type 2 Stickler syndrome (COL11A1 mutation). The position of maxilla and mandible relative to the cranial base was not significantly different from the reference population (S-N-A: p = 0.73, S-N-B: p = 0.43). The mandibular plane and y-axis showed an elevated angle with the cranial base in most patients, although not significant for the total group (S-N to Go-Me: p = 0.20, S-N to S-Gn: p = 0.18). Dental analysis was normal, except for a higher overjet value (p = 0.006) and a higher angle between occlusal plane and Frankfort plane (p = 0.022).
  
  
  CONCLUSIONS
  Cephalometric analysis was not able to thoroughly prove the abnormal facial appearance in Stickler syndrome. The majority of patients had normal dentofacial proportions. The most frequently observed anomaly in our series is a rather short and posteriorly rotated mandible, but clinical variability is high.
authors.affiliation: Department of Otorhinolaryngology, Ghent University/Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: frederic.acke@ugent.be.
authors.forename: Frederic R
authors.initials: FR
authors.lastname: Acke
authors.affiliation: Department of Otorhinolaryngology, Ghent University/Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
authors.forename: Ingeborg J
authors.initials: IJ
authors.lastname: Dhooge
authors.affiliation: Center for Medical Genetics, Ghent University/Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
authors.forename: Fransiska
authors.initials: F
authors.lastname: Malfait
authors.affiliation: Department of Otorhinolaryngology, Ghent University/Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
authors.forename: Els M R
authors.initials: EM
authors.lastname: De Leenheer
authors.affiliation: Department of Orthodontics, Ghent University/Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
authors.forename: Guy A M
authors.initials: GA
authors.lastname: De Pauw
mesh_terms: D000293:Adolescent; D000328:Adult; D001168:Arthritis / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D002508:Cephalometry; D002648:Child; D002972:Cleft Palate / Q000000981:diagnostic imaging / Q000473:pathology; D024161:Collagen Type XI / Q000172:deficiency* / Q000235:genetics; D003240:Connective Tissue Diseases / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D019066:Facies; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D006801:Humans; D008297:Male; D008334:Mandible / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D009154:Mutation; D012163:Retinal Detachment / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D020255:Vitreous Detachment / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D055815:Young Adult
chemical_list: D024161:Collagen Type XI
keywords: Cephalometrics; Micrognathia; Pierre Robin sequence; Stickler syndrome