How are borders of periapical radiolucent lesions often described radiographically?

• A. Radiopaque ring
• B. Well-defined or diffuse/blurred borders
• C. No borders visible
• D. Sharp, intact borders

Answer: (B)

The description of borders on a periapical radiolucent lesion reflects how clearly the lesion separates from surrounding bone. Often you’ll see a well-defined, corticated border where there’s a distinct, smooth margin between the lesion and normal bone, indicating a contained process. At other times the edge is diffuse or blurred, showing an irregular, poorly defined boundary due to active bone destruction and inflammatory infiltration. The radiographic border can vary with the lesion’s activity and stage, so describing borders as well-defined or diffuse/blurred covers the common appearances encountered.