Validity and Reliability of CBCT Derived 2D Perspective Cephalometric Images and 3D Orthogonal Imaging: A Comparative Evaluation

Abstract

The advancement in the field of three-dimensional imaging has overcome the limitations of conventional cephalometry. Presently, only few studies have been carried out to check the reliability and validity of CBCT. Aims:To compare (1) The difference between cephalometric angular and linear measurements in 3D orthogonal (3DO) and 2D perspective (2DP) which were CBCT synthesized cephalograms and (2) to verify the intra-and inter-reliability of the landmarks. Materials and methods:CBCT data of 50 patients was acquired using NEWTOM 3G. The Raw data sets (DICOM) were imported into Dolphin imaging version 10.5. Orthogonal and perspective time points were created and digitized. The results between the two were compared using a customized analysis.Results: Validity of the data was compared using the paired Student's t-test. The level of significance was 5% (p < 0.05). The 2D perspective was significantly different from 3D orthogonal in 21 of 29 parameters. Conclusion:Significant difference was observed between 2D perspective and 3D orthogonal attributing to the effect of magnification and distortion in 2D perspective projection. Intra-and Interoperator reliability of landmark identification in both 2D perspective and 3D orthogonal was in complete agreement with each other showing no significant difference.