title: Comparison of the accuracy of 3-dimensional cone-beam computed tomography and micro-computed tomography reconstructions by using different voxel sizes.
abstract: BACKGROUND
  Cone-beam computed tomography (CBCT) data are, in principle, metrically exact. However, clinicians need to consider the precision of measurements of dental morphology as well as other hard tissue structures. CBCT spatial resolution, and thus image reconstruction quality, is restricted by the acquisition voxel size. The aim of this study was to assess geometric discrepancies among 3-dimensional CBCT reconstructions relative to the micro-CT reference.
  
  
  METHODS
  A total of 37 permanent teeth from 9 mandibles were scanned with CBCT 9500 and 9000 3D and micro-CT. After semiautomatic segmentation, reconstructions were obtained from CBCT acquisitions (voxel sizes 76, 200, and 300 μm) and from micro-CT (voxel size 41 μm). All reconstructions were positioned in the same plane by image registration. The topography of the geometric discrepancies was displayed by using a color map allowing the maximum differences to be located.
  
  
  RESULTS
  The maximum differences were mainly found at the cervical margins and on the cusp tips or incisal edges. Geometric reconstruction discrepancies were significant at 300-μm resolution (P = .01, Wilcoxon test).
  
  
  CONCLUSIONS
  To study hard tissue morphology, CBCT acquisitions require voxel sizes smaller than 300 μm. This experimental study will have to be complemented by studies in vivo that consider the conditions of clinical practice.
authors.affiliation: Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, UMR 5288 CNRS, Toulouse, France; Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France. Electronic address: delphine_maret@yahoo.fr.
authors.forename: Delphine
authors.initials: D
authors.lastname: Maret
authors.affiliation: Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California.
authors.forename: Ove A
authors.initials: OA
authors.lastname: Peters
authors.affiliation: Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, UMR 5288 CNRS, Toulouse, France; Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Galibourg
authors.affiliation: Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, UMR 5288 CNRS, Toulouse, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Dumoncel
authors.affiliation: Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, UMR 5288 CNRS, Toulouse, France; Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France.
authors.forename: Rémi
authors.initials: R
authors.lastname: Esclassan
authors.affiliation: Institut d'Anatomie Normale de Strasbourg, Strasbourg, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Kahn
authors.affiliation: Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France; Laboratoire Universitaire LU 51: Maladies parodontales, déséquilibres systémiques et biomatériaux (MPDSB), Université Paul Sabatier, Toulouse, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Sixou
authors.affiliation: Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, UMR 5288 CNRS, Toulouse, France; Service de Médecine Légale, Hôpital de Rangueil, Toulouse, France.
authors.forename: Norbert
authors.initials: N
authors.lastname: Telmon
mesh_terms: D002675:Child, Preschool; D054893:Cone-Beam Computed Tomography / Q000706:statistics & numerical data*; D003481:Cuspid / Q000000981:diagnostic imaging; D003743:Dental Enamel / Q000000981:diagnostic imaging; D003804:Dentin / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data*; D021621:Imaging, Three-Dimensional / Q000706:statistics & numerical data*; D007180:Incisor / Q000000981:diagnostic imaging; D007223:Infant; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008963:Molar / Q000000981:diagnostic imaging; D014070:Tooth / Q000000981:diagnostic imaging*; D019237:Tooth Cervix / Q000000981:diagnostic imaging; D019228:Tooth Crown / Q000000981:diagnostic imaging; D014083:Tooth Germ / Q000000981:diagnostic imaging; D055114:X-Ray Microtomography / Q000706:statistics & numerical data*
keywords: Cone-beam computed tomography; reconstruction quality; voxel size; x-ray micro tomography