Figure 2.

A) The "Active contour segmentation mode" tool of ITK-SNAP software was used to select the region of interest (ROI); B, C) Semi-automatic segmentation of the bone rarefaction using "thresholding" and "edge attraction" tools; D) Segmentation of periapical bone rarefaction associated with #11; E, F) CBCT axial slices (T0) showing the segmentation of bone rarefactions related to teeth #11, #21, and #22; G) 3D virtual models of the lesions with volumetric analysis. (The color codes: Labels: 1-RED-PR tooth #11; 3-BLUE-Buccal radiolucency tooth #11; 4-YELLOW-PR tooth #22; 6-PINK-PR tooth # 21)