The periphery of the lesions can be Well-Defined or ill-Defined :
” A Well-Defined lesion is one in which most of the periphery is well-defined . these type of lesions may have one of these below peripheries “
“A punched-out border is one that has a sharp boundary or a very narrow zone of transition in which no bone reaction is apparent immediately adjacent to the abnormality. “ (more examples)
” A corticated margin is a thin , fairly fairly uniform radiopaque line of reactive bone at the periphery of a lesion . ” (more examples)
For example : Periapical Osseous Dysplasia Has Sclerotic border .
” A sclerotic margin represents a wider zone of transition made up of a thick radiopaque border of reactive bone that usually is not uniform in width .” (more examples)
For example : Cementoblastoma has Soft tissue capsule .
” A radiopaque lesion may have a soft tissue capsule , which is indicated by the presence of a radiolucent line at the periphery .” (more examples)
” An ill-defined lesion is one in which drawing periphery of it’s exact delineation ; is difficult . these type of lesions may have two kinds of periphery “
For example : Sclerosing osteitis has Blending border .
” A blending border is a gradual , often wide zone of transition between the adjacent normal bone trabeculae and the abnormal appearing trabeculae of the lesion . ” (more examples)
For example : Squamous cell carcinoma has Invasive border .
” An ill-defined invasive border appears as an area of radiolucency with few or no trabeculae representing bone destruction just behind and at the leading margin of the lesion and usually has a wide zone of transition.” (more examples)