title: Identification of cephalometric landmarks in unilateral cleft lip and palate patients: are there alternatives for point A, ANS, and PNS?
abstract: OBJECTIVE
  To test the reliability of some cephalometric measurements in unilateral cleft lip and palate patients. Measurements with A, ANS, and PNS, were compared to measurements performed with alternatives for point A, ANS, and PNS: A1, A2, ANS1, ANS2, and PNS1.
  
  
  METHODS
  One hundred sixty-four children with complete unilateral cleft lip and palate (UCLP), with a lateral head film taken at age 4 to 6 years.
  
  
  METHODS
  Intraobserver and interobserver reliability for cephalometric measurements including A, ANS, PNS or their alternatives: Dahlberg errors, systematic errors, and Pearson correlation coefficients were calculated.
  
  
  RESULTS
  The measurements using ANS and PNS or their alternatives, were comparable. The systematic error between observers for measurements using A2 was less than for measurements using A or A1. The scatterplot of point A showed a slightly better distribution of the points than the plots of A1 and A2.
  
  
  CONCLUSIONS
  Although the landmarks A, ANS, and PNS are hard to trace in UCLP patients with tooth germs in the anterior maxilla, no better landmarks were found in this study. Cephalometric studies using A, ANS, and PNS in UCLP patients should be interpreted with caution.
authors.affiliation: Department of Orthodontics and Oral Biology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Catharina A M
authors.initials: CA
authors.lastname: Bongaarts
authors.forename: Martin A
authors.initials: MA
authors.lastname: van't Hof
authors.forename: Birte
authors.initials: B
authors.lastname: Prahl-Andersen
authors.forename: Anne M
authors.initials: AM
authors.lastname: Kuijpers-Jagtman
mesh_terms: D000367:Age Factors; D002508:Cephalometry / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D002971:Cleft Lip / Q000000981:diagnostic imaging* / Q000628:therapy; D002972:Cleft Palate / Q000000981:diagnostic imaging* / Q000628:therapy; D005147:Facial Bones / Q000002:abnormalities / Q000000981:diagnostic imaging*; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008445:Maxillofacial Development; D011859:Radiography; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012886:Skull / Q000033:anatomy & histology / Q000000981:diagnostic imaging