title: Craniofacial shape differs in patients with tooth agenesis: geometric morphometric analysis.
abstract: OBJECTIVE
  To evaluate the shape of the craniofacial complex in patients with tooth agenesis and compare it to matched controls.
  
  
  METHODS
  The sample comprised 456 patients that were allocated to three groups: the agenesis group of 100 patients with at least one missing tooth, excluding third molars, the third molar agenesis group (3dMAG; one to four missing third molars) of 52 patients and the control group (CG) of 304 patients with no missing teeth. The main craniofacial structures depicted on lateral cephalograms were digitized and traced with 15 curves and 127 landmarks. These landmarks were subjected to Procrustes superimposition and principal component analysis in order to describe shape variability of the cranial base, maxilla and mandible, as well as of the whole craniofacial complex. For statistical analysis, permutation tests were used (10 000 permutations without replacement).
  
  
  RESULTS
  Approximately half of the sample's variability was described by the first three principal components. Comparisons within the whole sample revealed sexual dimorphism of the craniofacial complex and its structures (P < 0.01). Differences between the agenesis group and matched controls were found in the shape of all craniofacial structures except for the cranial base (P < 0.05). Specifically, patients with agenesis presented with Class III tendency and hypodivergent skeletal pattern. However, the comparison between the 3dMAG and matched CG revealed no differences.
  
  
  CONCLUSIONS
  The shape of the craniofacial complex differs in patients with tooth agenesis suggesting that common factors are implicated in tooth development and craniofacial morphology.
authors.affiliation: Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, Greece.
authors.forename: Alina
authors.initials: A
authors.lastname: Cocos
authors.affiliation: Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, Greece.
authors.forename: Demetrios J
authors.initials: DJ
authors.lastname: Halazonetis
mesh_terms: D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging / Q000473:pathology; D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks; D000848:Anodontia / Q000473:pathology*; D016022:Case-Control Studies; D002508:Cephalometry / Q000379:methods; D019465:Craniofacial Abnormalities / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D008964:Molar, Third / Q000002:abnormalities; D025341:Principal Component Analysis; D011859:Radiography; D019291:Skull Base / Q000473:pathology; D055815:Young Adult