The influence of secondary reconstruction slice thickness on NewTom 3G cone beam computed tomography–based
radiological interpretation of sheep mandibular condyle fractures


Objective. The objective of this study was to examine the diagnostic accuracy of the different secondary
reconstruction slice thicknesses of cone beam computed tomography (CBCT) on artificially created mandibular
condyle fractures.
Methods. A total of 63 sheep heads with or without condylar fractures were scanned with a NewTom 3G CBCT
scanner. Multiplanar reformatted (MPR) views in 0.2-mm, 1-mm, 2-mm, and 3-mm secondary reconstruction slice
thicknesses were evaluated by 7 observers. Inter- and intraobserver agreements were calculated with weighted kappa
statistics. The receiver operating characteristic (ROC) curve analysis was used to statistically compare the area under
the curve (AUC) of each slice thickness.
Results. The kappa coefficients varied from fair and to excellent. The AUCs of 0.2-mm and 1-mm slice thicknesses
were found to be significantly higher than those of 2 mm and 3 mm for some type of fractures.
Conclusion. CBCT was found to be accurate in detecting all variants of fractures at 0.2 mm and 1 mm. However, 2-
mm and 3-mm slices were not suitable to detect fissure, complete, and comminuted types of mandibular condyle
fractures.