Intentional Replantation of a Hopeless Mandibular Molar with a Combined Periodontal–Endodontic Lesion: A Case Report

Abstract

Intentional replantation (IR) is traditionally considered a last-resort procedure for teeth with an otherwise hopeless prognosis. Although advances in biomaterials have improved clinical outcomes, long-term evidence in teeth with combined periodontal–endodontic lesions (CPEL) and severe mobility remains limited. This case report describes a 12-year outcome of IR in a mandibular molar with a large CPEL, Grade III mobility, and persistent infection despite previous root canal therapy (RCT). A 45-year-old female presented with persistent pain and a draining sinus tract associated with tooth #36 one month after an RCT performed elsewhere. Clinical examination revealed Grade III mobility, probing depths >6 mm, bleeding on probing, and Class III furcation involvement. Radiography showed extensive periradicular and furcal radiolucency (PAI = 5). After obtaining written informed consent, an IR was performed. Atraumatic extraction was followed by root-end resection, retro-preparation using Gates-Glidden burs, and placement of calcium-enriched mixture (CEM) cement as a root-end filling material. The tooth was replanted within 9 minutes. No splinting was used. At two weeks, the infection had resolved, and mobility decreased to Grade II. Complete radiographic healing was observed at 3 years (PAI = 1). Probing depths normalized (<3 mm), mobility resolved (Grade 0), and no root resorption or ankylosis occurred. Follow-ups at 4, 5, 6, and 12 years confirmed long-term stability. At 12 years, recurrent coronal caries was restored with an amalgam crown featuring intra-orifice barriers. Periapical health, periodontal architecture, and function remained intact. This 12-year follow-up demonstrates that, when executed with strict biological principles and biomaterial selection, IR can achieve long-lasting success even in teeth with multiple negative prognostic indicators. The result highlights CEM cement as a biocompatible, bioactive root-end filling material that may promote periradicular healing in compromised conditions.