Figure 4

(a) Correlations among the VCA angle in the CT sagittal plane and the ACEA on the FP radiograph with neutral rotation. (b) The receiver operating characteristic curve for inadequate anterior coverage with the ACEA in FP radiograph. The cut-off value of the ACEA was 13.6° (sensitivity 69%, specificity 89%, area under the curve 0.85). VCA Vertical-center-anterior, ACEA Anterior center edge angle, FP False profile.