Radiology · single question
A patient has a mesio-occlusal caries that is painful on percussion. The thermal test causes lingering pain. What radiograph is MOST indicated?
Show answer and explanation
Correct answer: B. Periapical radiograph
Pain on percussion + lingering pain to thermal test indicates irreversible pulpitis or periapical pathology. The periapical radiograph is the MOST appropriate because it shows the ENTIRE tooth from crown to apex, including the periapical region, allowing visualization of: root anatomy, periapical pathology (radiolucency, widened PDL space), root resorption, and furcation involvement. Bitewings show only crowns/crestal bone — they miss apical pathology.
- A. CORRECT. A periapical X-ray is essential for any tooth with signs of pulpal/periapical pathology — it visualizes the entire root and apex where pathology will appear.
- B. Incorrect. Bitewings show the crowns and crestal bone but do NOT capture the apical region where periapical pathology occurs.
- C. Incorrect. A panoramic X-ray provides an overview but lacks the detail needed for periapical diagnosis of a specific tooth.
- D. Incorrect. CBCT provides 3D imaging and is useful in complex cases, but a periapical radiograph is the first-line, standard diagnostic for pulpal/periapical evaluation.