An incidental finding was spotted on both periapical films taken at different angulations, labeled with red arrows. What are the arrows pointing to?

Correct answer: C. Coronoid process

• A. A supernumerary tooth would itself be a distinct tooth-shaped radiopacity, not a normal anatomic landmark that shifts position with the angle of the film.
• B. Osteosarcoma would show an aggressive, ill-defined lesion (often with a 'sunburst' pattern) — not a normal structure seen on two different periapical angulations.
• C. Correct. The coronoid process of the mandible can be superimposed over the maxillary molar region on periapical films, and because it is a normal anatomic structure it appears to move/shift between films taken at different horizontal angulations — the classic clue for this finding.
• D. A ghost image from jewelry would not appear consistently in the same general area on two periapical exposures taken with different angulation, and would have a distinct metallic radiopaque shape.

Note: In the actual exam, the process is not labeled — they only ask 'What is seen on the X-ray?' (periapical film).