Endodontics · single question
What is the COMBINED pulpal and periapical diagnosis of a tooth with a CHRONIC draining sinus tract?
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Correct answer: C. Pulp necrosis / chronic apical abscess (asymptomatic apical abscess with sinus tract)
A draining sinus tract indicates: (1) The pulp is NECROTIC — vital pulp does not cause periapical abscess. (2) Periapical diagnosis: CHRONIC APICAL ABSCESS / asymptomatic apical abscess — infection has established a drainage pathway (sinus tract). This is typically PAINLESS because pressure is relieved by drainage. The sinus tract is pathognomonic for chronic apical abscess.
- A. ❌ Irreversible pulpitis implies a still-vital, inflamed pulp — incompatible with a draining sinus tract.
- B. ❌ Symptomatic apical periodontitis is acute and painful without drainage — incompatible with a chronic sinus tract.
- C. ✅ Pulp necrosis + chronic apical abscess (asymptomatic apical abscess with sinus tract) — the correct combined diagnosis.
- D. ❌ Normal pulp cannot produce a periapical abscess or sinus tract.