Effects of cone-beam computed tomography with different FOV parameters on simulated internal root resorption volume

The aim of this in-vitro study was to verify which field of view (FOV) in cone-beam computed tomography (CBCT) yields greater accuracy in the detection of internal root resorption (IRR) volume, in comparison to the gold standard of micro-computed tomography (micro-CT) and to a physical method. Twenty-five extractedsingle-rooted teeth were scanned by CBCT with two different FOV parameters (6x6-FOV and 10x10-FOV) and via micro-CT. The volume of dental hard tissue was measured on these images. A simulated IRR was produced by a demineralization protocol. After the simulated IRR, the volumes of the dental hard tissue and the simulated IRR were measured with the same scanning parameters. In addition, the volume of the simulated IRR was measured via a physical method. The simulated IRR volumes obtained by CBCT, micro-CT, and the physical method were statistically compared using one-way ANOVA. Before the simulated IRR, the mean volume of dental hard tissue obtained by 6x6-FOV, 10x10-FOV, and micro-CT were 266.64 ± 11.56, 284.78 ± 14.99, and 233.07 ± 19.91, respectively. The simulated IRR mean volumes obtained by 6x6-FOV, 10x10-FOV, micro-CT, and the physical method were 19.35 ± 5.92, 17.43 ± 5.20, 23.85 ± 6.63, and 13.51 ± 3.11, respectively. The mean volume of the simulated IRR obtained by micro-CT was similar to that of the 6x6-FOV and was significantly different from that of the 10x10-FOV and physical method. The mean volume value of simulated IRR obtained by the physical method was significantly different from those of the micro-CT and 6x6-FOV groups. In conclusion, the 6x6-FOV was better than the 10x10-FOV for the detection of IRR volume by CBCT under clinical conditions.