Given the intact coronal seal, what is generally the first-line treatment approach?
Case
A tooth with a technically well-obturated root canal continues to show a persistent periapical radiolucency at 1-year follow-up. The coronal restoration is intact and well-sealed.
Explanation
When the coronal seal is intact but a periapical lesion persists, the more likely cause is a missed canal, untreated isthmus, or persistent intracanal infection rather than a purely extraradicular problem. Nonsurgical retreatment addresses this directly and is generally attempted before surgery. Apicoectomy is reserved for cases where retreatment isn't feasible — for example, a post and core that can't be safely removed — or has already failed.
Clinical Pearl
An intact coronal restoration doesn't rule out missed canal anatomy. The MB2 canal in maxillary molars is the single most commonly missed canal behind a persistent lesion.
Reference: AAE retreatment vs. surgery guidelines