title: 3-D volume rendering maxillofacial analysis of angular measurements by multislice CT.
abstract: OBJECTIVE
  This study was designed to determine the precision and accuracy of angular measurements using three-dimensional computed tomography (3D-CT) volume rendering by computer systems.
  
  
  METHODS
  The study population consisted of 28 dried skulls that were scanned with a 64-row multislice CT, and 3D-CT images were generated. Angular measurements, (n = 6) based upon conventional craniometric anatomical landmarks (n = 9), were identified independently in 3D-CT images by 2 radiologists, twice each, and were then performed by 3D-CT imaging. Subsequently, physical measurements were made by a third examiner using a Beyond Crysta-C9168 series 900 device.
  
  
  RESULTS
  The results demonstrated no statistically significant difference between interexaminer and intraexaminer analysis. The mean difference between the physical and 3-D-based angular measurements was -1.18% and -0.89%, respectively, for both examiners, demonstrating high accuracy.
  
  
  CONCLUSIONS
  Maxillofacial analysis of angular measurements using 3D-CT volume rendering by 64-row multislice CT is established and can be used for orthodontic and dentofacial orthopedic applications.
authors.affiliation: Department of Social Dentistry, College of Dentistry, Centro Universitário de João Pessoa, João Pessoa, Brazil.
authors.forename: Patricia M L
authors.initials: PM
authors.lastname: Lopes
authors.forename: Carla R
authors.initials: CR
authors.lastname: Moreira
authors.forename: Andréia
authors.initials: A
authors.lastname: Perrella
authors.forename: José L
authors.initials: JL
authors.lastname: Antunes
authors.forename: Marcelo G P
authors.initials: MG
authors.lastname: Cavalcanti
mesh_terms: D000328:Adult; D002102:Cadaver; D002508:Cephalometry / Q000379:methods*; D005147:Facial Bones / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012016:Reference Values; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*