title: Reliability of the integrated radiograph-photograph method to obtain natural head position in cephalometric diagnosis.
abstract: OBJECTIVE
  To introduce a simple and reliable method to reorient lateral radiographs to the natural head position (NHP) according to standardized photographs made at NHP.
  
  
  METHODS
  The study has two parts. In the first part, 45 patients were randomly selected from a patient cohort. Photographs (at NHP) and cephalograms from each patient were taken and assessed in two sessions by two observers. The time between the first and the second session was 5 weeks. The repeatability of profile measurements on cephalograms compared with standardized photographs of the same patient was determined; in the second part, the repeatability of three superimposing protocols (ie, the soft tissue N/subnasale line [V-line], the esthetic line [E-line], and a proposed nose best fit line [N-line]) was compared for the reorientation of the cephalogram according to the photographs made at the NHP.
  
  
  RESULTS
  Our results showed that the integration of radiographs and photographs is an objective and reliable method to obtain NHP in lateral cephalograms. The N-line is a reproducible and stable reference line for the reorientation of radiographs to obtain NHP.
  
  
  CONCLUSIONS
  Reorientation of radiographs according to standardized photographs made at the NHP is a reliable and objective method to standardize the radiographs at the NHP for cephalometric analysis. The N-line is a reproducible and stable reference line for the reorientation. It is preferred over the V-line or even E-line, especially when the radiographs and photographs are taken at different sessions or at different treatment stages.
authors.affiliation: Department of Orthodontics, University Medical Centre Groningen, University of Groningen, The Netherlands.
authors.forename: Dima P
authors.initials: DP
authors.lastname: Dvortsin
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Ye
authors.forename: Gerard J
authors.initials: GJ
authors.lastname: Pruim
authors.forename: Pieter U
authors.initials: PU
authors.lastname: Dijkstra
authors.forename: Yijin
authors.initials: Y
authors.lastname: Ren
mesh_terms: D059925:Anatomic Landmarks / Q000033:anatomy & histology; D002508:Cephalometry / Q000379:methods* / Q000592:standards; D002680:Chin / Q000033:anatomy & histology; D015331:Cohort Studies; D004955:Esthetics, Dental; D005145:Face / Q000033:anatomy & histology; D005624:Frontal Bone / Q000033:anatomy & histology; D006257:Head / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008046:Lip / Q000033:anatomy & histology; D009666:Nose / Q000033:anatomy & histology; D010781:Photography / Q000379:methods* / Q000592:standards; D011187:Posture; D012015:Reference Standards; D015203:Reproducibility of Results; D012984:Software