title: Anatomical shape analysis of the mandible in Caucasian and Chinese for the production of preformed mandible reconstruction plates.
abstract: OBJECTIVE
  The purpose of this study was to evaluate and analyze statistical shapes of the outer mandible contour of Caucasian and Chinese people, offering data for the production of preformed mandible reconstruction plates.
  
  
  METHODS
  A CT-database of 925 Caucasians (male: n=463, female: n=462) and 960 Chinese (male: n=469, female: n=491) including scans of unaffected mandibles were used and imported into the 3D modeling software Voxim (IVS-Solutions, Chemnitz, Germany). Anatomical landmarks (n=22 points for both sides) were set using the 3D view along the outer contour of the mandible at the area where reconstruction plates are commonly located. We used morphometric methods for statistical shape analysis.
  
  
  RESULTS
  We found statistical relevant differences between populations including a distinct discrimination given by the landmarks at the mandible. After generating a metric model this shape information which separated the populations appeared to be of no clinical relevance. The metric size information given by ramus length however provided a profound base for the production of standard reconstruction plates.
  
  
  CONCLUSIONS
  Clustering by ramus length into three sizes and calculating means of these size-clusters seem to be a good solution for constructing preformed reconstruction plates that will fit a vast majority.
authors.affiliation: Department of Craniomaxillofacial Surgery, Albert-Ludwig University Freiburg, Hugstetter Straße 55, D-79106 Freiburg, Germany. Marc_Metzger@gmx.net
authors.forename: Marc C
authors.initials: MC
authors.lastname: Metzger
authors.forename: Mathias
authors.initials: M
authors.lastname: Vogel
authors.forename: Bettina
authors.initials: B
authors.lastname: Hohlweg-Majert
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Mast
authors.forename: Xianqun
authors.initials: X
authors.lastname: Fan
authors.forename: Alexandra
authors.initials: A
authors.lastname: Rüdell
authors.forename: Stefan
authors.initials: S
authors.lastname: Schlager
mesh_terms: D000704:Analysis of Variance; D059925:Anatomic Landmarks; D044466:Asian People; D001860:Bone Plates; D002508:Cephalometry; D016000:Cluster Analysis; D003198:Computer Simulation; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D025341:Principal Component Analysis; D011474:Prosthesis Design; D019651:Plastic Surgery Procedures / Q000295:instrumentation*; D044465:White People