Head and Neck ImagingCortical niche sign
indentation along the inner margin of the lingual mandibular cortex, created by the mandibular nerve as it traverses the mandible. It is seen on orthogonal image reconstructions of axial
CT images of the mandible, created during preoperative evaluation for placement of
dental implants. This indentation can be subtle or absent. When present, it is seen on several consecutive cross-sectional images. The cortical niche sign helps to identify a mandibular canal with poorly
calcified margins.
RH