Persistent apical periodontitis after root canal treatment — ORE Part 1 MCQ

Instant feedback + full explanation. One question, done properly.

HardRestorative DentistryPersistent apical periodontitis after root canal treatmentORE Part 1

A 48-year-old patient has a sinus tract adjacent to a root-filled upper lateral incisor. A gutta-percha point traces to the apex, and the periapical radiograph shows a short, poorly condensed root filling with a periapical radiolucency. The tooth has a satisfactory coronal restoration and adequate periodontal support. What is the most appropriate initial treatment?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Non-surgical root canal retreatment

Non-surgical root canal retreatment is the evidence-based first-line treatment for persistent apical periodontitis. This case presents optimal prognostic factors: a short, poorly condensed filling (identifiable technical cause remediable by retreatment), satisfactory coronal restoration, and adequate periodontal support. Retreatment success rates in contemporary series are 78–83% with expert technique, and are significantly higher when coronal seals are intact. Option B (apical surgery) is reserved for cases where retreatment has failed or cannot be performed. Option A (extraction) is not appropriate for a restorable tooth with a single technical deficiency. Option D (antibiotics) does not address the mechanical cause of failure. Option C (observation) ignores the active sinus tract and radiographic lesion requiring definitive treatment. The short, condensation-deficient filling is specifically remediable by retreatment, making it the optimal starting point in the treatment hierarchy.

Reference: Clinical Outcomes of Nonsurgical Retreatment in Teeth With Persistent Apical Periodontitis: A Systematic Review. JADA (2025); NCT systematic review. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12776209/; Factors influencing the outcome of nonsurgical root canal treatment and retreatment: A retrospective study. J Endod (2024). https://pubmed.ncbi.nlm.nih.gov/38214429/