Radiology · patient case question
One periapical in the series shows the linear radiolucent band seen here running across the image. What has caused it?
Patient case: Routine radiographic survey
Patient: Male, 34 years old
Chief complaint: “I'm just here for my check-up.”
History: No significant medical history. No medications. Last radiographs five years ago.
Findings: A panoramic radiograph and a full-mouth periapical series are taken today. Several incidental findings are noted for discussion.
Show answer and explanation
Correct answer: C. A processing or handling artifact from bending the receptor
- A. A dentinal or root fracture line stays confined to the tooth, follows the long axis or an oblique plane within it, and does not run out across the bone and beyond the image.
- B. Cervical burnout is a diffuse, ill-defined radiolucent zone at the CEJ between the enamel edge and the alveolar crest, caused by the abrupt change in absorbing thickness. It is a triangular shadow, not a linear band.
- C. CORRECT. A sharp, linear or crescentic radiolucent band that crosses anatomic structures without respecting them is an ARTIFACT. Bending or creasing the film or a flexible phosphor plate cracks the emulsion and produces exactly this thin dark line. It is recognised by the fact that it ignores anatomy — a real structure has to belong to something.
- D. A cone-cut is a clear-cut CURVED border with total absence of exposure beyond it, produced when the beam misses part of the receptor. It appears as a blank region, not a line.
Note: The habit worth building: any finding that crosses anatomic boundaries as though they weren't there is an artifact until proven otherwise. Retake rather than interpret.