Peri-radicular surgery is primarily indicated to remove persistent periapical pathology after root canal treatment, gain surgical access for retrograde filling, or extract fractured root fragments beyond the apex that cannot be managed nonsurgically. However, it is not performed solely to improve the apical seal; this is typically achieved through conventional root canal retreatment or retrograde filling during surgery. The goal of surgery is to address pathological or mechanical issues unresolvable by nonsurgical means, rather than to enhance the seal without evidence of ongoing pathology.

Reference: Pathways of the Pulp, 12th Edition.