title: Tuned-aperture computed tomography for detection of occlusal caries.
abstract: OBJECTIVE
  To evaluate the use of tuned-aperture computed tomography (TACT) for the detection of primary occlusal caries.
  
  
  METHODS
  The material comprised 76 extracted posterior teeth, 51 with caries. Radiographs were recorded both with the Sens-A-Ray (Regam Medical Systems Int. AB, Sundsvall, Sweden) digital radiographic system and with Kodak EktaSpeed Plus film (Eastman-Kodak Co., Rochester NY, USA) employing an Orthopantomograph OP 100 (Instrumentarium Imaging, Tuusula, Finland) and a Prostyle Intra (Planmeca, Helsinki, Finland) dental unit respectively. The Sens-A-Ray radiographs were used to construct TACT slices and TACT iterative slices. The teeth were subsequently sectioned in 300 microm thick slices. Microradiographs were exposed and analysed with respect to the true presence of lesions. Seven observers subjectively evaluated the radiographs and ROC analyses performed. Conventional radiographs were compared with TACT images by means of the area under the ROC curves, Az. Paired t-test was used to compare Az values. Interobserver agreement was evaluated using the Kendall coefficient and the Friedman Anova.
  
  
  RESULTS
  TACT radiographs were significantly better than conventional radiographs for diagnosing all types of occlusal caries combined (P(TACT) (slices)=0.02. P(TACT) (iterative slices)=0.01). However, neither TACT system was significantly better than film for enamel and dentinal caries separately. Observer agreement was moderate. However, observers demonstrated significant systematic differences in their readings (P<0.001).
  
  
  CONCLUSIONS
  TACT may be a feasible method for diagnosing primary occlusal caries.
authors.affiliation: Department of Oral Radiology, Institute for Odontology, Karolinska Institute, Huddinge, Sweden.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Shi
authors.forename: P
authors.initials: P
authors.lastname: Han
authors.forename: U
authors.initials: U
authors.lastname: Welander
authors.forename: B
authors.initials: B
authors.lastname: Angmar-Månsson
mesh_terms: D000704:Analysis of Variance; D001641:Bicuspid; D003731:Dental Caries / Q000000981:diagnostic imaging*; D006801:Humans; D008963:Molar; D015588:Observer Variation; D012372:ROC Curve; D019252:Radiography, Dental, Digital; D011862:Radiography, Panoramic; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*