BL was used as the first volume, displayed in white, with T1 added as the second volume, displayed in yellow (planes A, B, C). The superimposition was performed using Voxel-based superimposition feature with a red cube set in the area of interest (maxilla in planes A, B, C). Finer alignment was achieved by marking a sub-region for auto-superimposition (plane D). Annotations were made using the digitize/measurement feature. The distance between landmarks was automatically calculated and displayed as vertical and horizontal 2D lines for BL (plane E) and T1 (plane f).