Endodontics · single question
A 'J-shaped' radiolucency on a periapical radiograph is associated with which condition?
Show answer and explanation
Correct answer: A. Vertical root fracture
- A. A J-shaped (or 'halo') periapical radiolucency — extending from the periapex along the lateral aspect of the root — is the classic radiographic pattern of a VERTICAL ROOT FRACTURE. The fracture allows bacterial ingress both apically and laterally, creating this distinctive 'J' shape.
- B. Horizontal root fracture shows a horizontal radiolucent line crossing the root — not a J-shaped radiolucency.
- C. A periapical abscess creates a radiolucency at the ROOT APEX only — not the lateral J-shaped extension typical of vertical root fracture.
- D. External root resorption creates irregular radiolucent areas AT the root surface — the J-shaped combined periapical + lateral radiolucency is specific to vertical root fracture.