Retrospective evaluation of mandibular third molars using simulated low-dose cone-beam computed tomography: A comparative image quality study

Purpose: This study was performed to establish a procedure for simulated low-dose cone-beam computed tomography (CBCT) scans and to investigate whether the resulting images are comparable in diagnostic accuracy to those obtained using a clinical low-dose protocol.Materials and Methods: ImageJ was used to manipulate the sinogram data from CBCT scans acquired at 5 mA to mimic a technical setting of 2 mA by adding noise to the Radon-transformed projection data before image reconstruction.Four observers compared the simulated 2 mA CBCT scans with original clinical 2 mA CBCT scans acquired previously.The CBCT images were analysed using a protocol with a ranking scale, and the observers were required to select only 1 category for each variable.The Wilcoxon signed-rank test was used to assess differences between the 2 CBCT scan types, with a significance level of P