title: Does a combination of two radiographs increase accuracy in detecting acid-induced periapical lesions and does it approach the accuracy of cone-beam computed tomography scanning?
abstract: BACKGROUND
  The purpose of this study was to determine whether the use of a combination of 2 images (storage phosphor plates [SPPs] and F-speed films [Eastman Kodak, Rochester, NY]) with a 10° difference in horizontal beam angulation resulted in better detectability of chemically created periapical defects than when only 1 image was used and whether a detectability as good as that achieved by limited cone-beam computed tomography (LCBCT) scanning could be achieved.
  
  
  METHODS
  Lesions were created by 1, 1.5, and 2 hours of acid application apical to extracted teeth in jaw specimens. After repositioning, teeth were radiographed with Accu-I-Tomo LCBCT, Digora Optime SPP system, and F-speed films. The SPPs and films were exposed at 0° and 10° horizontal angulations. The diagnostic accuracy (Az) was compared using 2-way analysis of variance; pair-wise comparisons were performed using the post hoc t test. Kappa was used to measure interobserver agreement.
  
  
  RESULTS
  A combination of 2 exposures with a 10° difference in horizontal angulation caused an increase, although not statistically significant, in the accuracy of both films and SPPs for all acid durations (P > .05) compared with when only 1 exposure was used. The accuracy did not approach that of LCBCT.
  
  
  CONCLUSIONS
  Using a combination of 2 exposures instead of 1 did not significantly increase the accuracy in detecting acid-induced lesions at the apices of single-rooted premolars. The accuracy of LCBCT was superior.
authors.affiliation: Department of Oral Diagnosis and Radiology, School of Dentistry, Ege University, Izmir, Turkey. esogur@yahoo.com
authors.forename: Elif
authors.initials: E
authors.lastname: Soğur
authors.forename: Hans-Göran
authors.initials: HG
authors.lastname: Gröndahl
authors.forename: B Güniz
authors.initials: BG
authors.lastname: Baksı
authors.forename: Ali
authors.initials: A
authors.lastname: Mert
mesh_terms: D001641:Bicuspid / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods* / Q000592:standards; D006801:Humans; D010472:Perchlorates / Q000009:adverse effects; D010483:Periapical Diseases / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000379:methods* / Q000592:standards; D016300:Radiography, Bitewing / Q000379:methods* / Q000592:standards; D019252:Radiography, Dental, Digital / Q000379:methods / Q000592:standards; D013997:Time Factors; D019227:Tooth Apex / Q000000981:diagnostic imaging; D020390:Tooth Socket / Q000000981:diagnostic imaging / Q000187:drug effects; D014962:X-Ray Film; D014963:X-Ray Intensifying Screens
chemical_list: D010472:Perchlorates