Which radiographic description best fits focal periapical osteopetrosis?

• A. Radiopaque halo around root apex
• B. Variable radiopacity in size/shape; well defined to diffuse margins
• C. No radiographic changes
• D. Uniform radiolucency at the apex

Answer: (B)

Focal periapical osteopetrosis presents as localized increased bone density around a tooth root due to impaired osteoclast resorption. On radiographs, this appears as a dense, radiopaque area at the periapex, and importantly, its appearance can vary in size and shape with margins ranging from well defined to diffusely marginated. That variability in opacity and the potential range from sharp to fuzzy borders is exactly what the description captures. This distinguishes it from radiolucent periapical lesions (which would look darker) or from a simple uniform radiopaque halo that doesn’t convey the possible range of margins around the apex.