Retreatment of Tooth 26 – 2-Year Follow-Up

This case presents a challenging endodontic retreatment of tooth 26, indicated by the development of apical periodontitis in conjunction with a distal marginal gap identified in the existing crown. Marginal leakage is a well-recognised risk factor for endodontic failure, and the combination of periapical pathology with a compromised coronal seal provided a clear rationale for nonsurgical retreatment rather than extraction. Clinical Findings Pre-operative clinical and radiographic assessment revealed apical periodontitis associated with tooth 26. The existing crown displayed a distal marginal gap, raising the suspicion of bacterial re-contamination of the root canal system. Review of the original treatment identified an inadequately obturated canal anatomy, with the mesiobuccal second (MB2) canal not previously located or treated — a finding frequently associated…