title: 3D volume rendering using multislice CT for dental implants.
abstract: OBJECTIVE
  To determine the precision and accuracy of three-dimensional (3D) volume rendering spiral multislice computed tomography (CT)-based linear measurements of the mental foramen for dental implants, in vitro, and their precision, in vivo.
  
  
  METHODS
  Five cadaver heads were imaged by multislice spiral CT (Toshiba Aquilion) with 0.5 mm thick axial slices (0.5 mm/0.5 s of table feed) at 0.5 mm interval reconstructions. The image data sets were transferred to a networked computer workstation. Using computer graphics the data were analysed with a 3D volume rendering technique using Vitrea software. Two oral and maxillofacial radiologists, independently, made electronic linear measurements from the superior border of the mental foramen to the crest of the alveolar process. The soft tissues were removed and physical measurements made using a 3 Space (Polhemus, Colchester, VT, USA) electromagnetic digitizer with a personal computer running Windows 98. The same linear measurements of 15 patients using the same imaging methodology were performed and the precision was analysed.
  
  
  RESULTS
  The findings showed no statistically significant inter- or intra-observer differences in vitro and in vivo, or between imaging and physical measurements in vitro (P>0.05).
  
  
  CONCLUSIONS
  3D multislice spiral CT imaging allows highly accurate measurements for dental implant placement in proximity to the mental foramen. Computer graphics software, using volume rendering is suitable for implant planning.
authors.affiliation: Department of Radiology, Faculty of Odontology, University of São Paulo, Brazil. mgpcaval@usp.br
authors.forename: M G P
authors.initials: MG
authors.lastname: Cavalcanti
authors.forename: A
authors.initials: A
authors.lastname: Ruprecht
authors.forename: M W
authors.initials: MW
authors.lastname: Vannier
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D002680:Chin / Q000000981:diagnostic imaging; D003196:Computer Graphics; D003758:Dental Implantation, Endosseous; D006801:Humans; D021621:Imaging, Three-Dimensional; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging*; D008334:Mandible / Q000000981:diagnostic imaging; D008875:Middle Aged; D010347:Patient Care Planning; D019252:Radiography, Dental, Digital; D015203:Reproducibility of Results; D036542:Tomography, Spiral Computed / Q000379:methods*