title: Image artifact in dental cone-beam CT.
abstract: OBJECTIVE
  The purpose of this study was to investigate the appearance and possible cause of an artifact seen in limited-volume cone-beam CT imaging.
  
  
  METHODS
  A water-filled plastic cylinder was used as a phantom of the head. A test object was constructed as a bone-equivalent phantom to be imaged. The test object was variously positioned at the center of the phantom and near its margins. CT images of the test object were acquired using a 3DX Accuitomo system.
  
  
  RESULTS
  In slice images with the test object positioned near the margin of the phantom, arch-shaped defects or deformities were observed on the side of the object. There was a negative correlation between the artifact and the CT value of the object. The artifact was larger in images scanned with a higher voltage.
  
  
  CONCLUSIONS
  The probability that this artifact is caused by halation from the image intensifier (II) system is suggested.
authors.affiliation: Department of Oral Radiology, Asahi University School of Dentistry, Gifu, Japan. kawamata@dent.asahi-u.ac.jp
authors.forename: Akitoshi
authors.initials: A
authors.lastname: Katsumata
authors.forename: Akiko
authors.initials: A
authors.lastname: Hirukawa
authors.forename: Marcel
authors.initials: M
authors.lastname: Noujeim
authors.forename: Shinji
authors.initials: S
authors.lastname: Okumura
authors.forename: Munetaka
authors.initials: M
authors.lastname: Naitoh
authors.forename: Masami
authors.initials: M
authors.lastname: Fujishita
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Ariji
authors.forename: Robert P
authors.initials: RP
authors.lastname: Langlais
mesh_terms: D016477:Artifacts; D006801:Humans; D019047:Phantoms, Imaging; D011861:Radiography, Dental / Q000379:methods; D036542:Tomography, Spiral Computed; D014963:X-Ray Intensifying Screens