The reliability of cone-beam computed tomography (CBCT) - Generated frontal cephalogramsq

Background: The purpose of this study was to evaluate the reliability of measurements from cone-beam computed tomography (CBCT)-generated frontal cephalogram. Materials and methods: CBCT and conventional posteroanterior (PA) cephalograms were taken from 30 adult patients. CBCT image was set according to the Frankfurt-Horizontal (FH) plane as the horizontal plane and the midsagittal reference (MSR) plane. The CBCT frontal cephalograms were generated using the orthogonal Raycast method (group CTraycast), the orthogonal maximum intensity projection (MIP) method (group CTMIP) after the head reorientation according to the reference planes, and the generator tool provided by the employed 3-dimensional (3D) imaging software (group CTgenerator), respectively. The differences between the CBCT-generated frontal cephalograms and conventional PA cephalograms (group PA(ceph)) were compared by paired t-test (p < 0.05). Results: The significant differences were shown in two measurements for group CTraycast, in 12 measurements for group CTMIP, and in eight measurements for group CTgenerator. It was confirmed that the CBCT frontal cephalograms, generated by means of the Raycast method (Group CTraycast), were more comparable to the conventional PA cephalograms in their measurements than were the others (Groups CTMIP, CTgenerator). Conclusion: This study may well suggest that frontal cephalograms derived by 3D CBCT reorientation can be effectively employed in clinical applications. (C) 2012 European Association for Cranio-Maxillo-Facial Surgery.