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?

Introduction: 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 [East-man Kodak, Rochester, NY]) with a 10 degrees 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 radio-graphed with Accu-l-Tomo LCBCT, Digora Optime SPP system, and F-speed films. The SPPs and films were exposed at 0 degrees and 10 degrees 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 degrees 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. (J Endod 2012;38:131-136)