Endodontics · single question
A patient has pain on biting tooth #19 (previously root-canal-treated). A sinus tract traced with gutta-percha points to the furcation. What is the MOST likely diagnosis?
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Correct answer: B. Vertical root fracture with furcation extension
Sinus tract tracing to the furcation in a previously RCT-treated tooth is pathognomonic of vertical root fracture.
- A. Iatrogenic perforation during RCT would have been apparent at the time of treatment. Vertical fracture is more consistent with this presentation.
- B. CORRECT. Vertical root fracture is the most likely diagnosis when a sinus tract from an RCT-treated tooth traces to the furcation. This classic presentation (furcation-directed sinus tract + pain on biting + existing RCT) is pathognomonic of vertical root fracture.
- C. Periodontal disease can cause furcation involvement but would not typically produce a sinus tract in an RCT-treated tooth with pain on biting.
- D. Failed RCT with periapical abscess would show a sinus tract tracking to the APEX, not the furcation.