Endodontic Retreatment Of Mandibular Incisors With Root Canals Variations

Mandibular incisors have been found to have a complex anatomy of the root canal system. Missed root canals are the most likely cause of treatment failure, and the persistent intra-radicular infections can lead to periapical lesion and toothlessness. This article reports a rare case of the mandibular incisors with two root canals complicated by periapical cysts after root canal treatment. After systematic refinement of the root canal retreatment, the cyst had completely healed at the 3-year follow-up. A 29-year-old female with a periapical mandibular cyst required surgical treatment. Clinical examination revealed that the right mandibular incisors were filled with resin. The left mandibular central incisor was discolored. Cone-beam computed tomography (CBCT) imaging revealed a large periapical cyst (3×6×7.9 mm) extending from the left central mandibular incisor to the right lateral incisor. Radiological evidence showed that the lingual root canal was inadequately treated. Root canal retreatment and endodontic microsurgery was performed to eliminate the inflammation. After a 6-month follow-up, new bone formation and mandibular incisors was completely asymptomatic. Finally, ceramic crown restoration was performed. Two root canals with Vertucci Type IV morphology were identified in the mandibular incisors. Complete debridement and shaping of the root canal system to remove inflammatory substances is important for root canal retreatment. Variations in the incisor root canal can be effectively detected using CBCT and endodontic microscopy. Systemic management, including reintervention of the missed root canal and microsurgery, can achieve healing of extensive periapical cysts.