Figure 1

Schematic representation of two methods. Schematic diagram showing distances of two bony landmarks measured in the transverse plane from 3D cone-beam computed tomography (CBCT) data (A1, A2, B1 and B2) and from 2D images projected from the 3D CBCT data (Image plane: C1, C2, D1 and D2; mid-sagittal plane: A1’, A2’, B1’ and B2’) at two instances during growth. Differences in the bony landmark positions and the angles between the inter-landmark line segment and image plane lead to different errors in the 2D measurements of the inter-landmark distances, even though the images were scaled to the mid-sagittal plane and the magnification factor was taken into consideration.