A 35-year-old male has pain on biting tooth #9 (upper left central). Radiograph shows existing root canal treatment and an abscess traced with gutta percha. What is the diagnosis?

Correct answer: C. Irreversible pulpitis

• A. Incorrect. A previously root canal-treated tooth has no vital pulp — pulpitis diagnoses cannot apply.
• B. Incorrect. Same reasoning — no vital pulp in a previously treated tooth.
• C. Correct. A previously root canal-treated tooth with a sinus tract (traced with gutta percha) and pain on biting represents pulp necrosis/failed RCT with periapical pathology.
• D. Incorrect. An existing sinus tract confirms periapical pathology — this is not a normal periapical state.