A Decade of Survival after Intracanal Repair of External Cervical Resorption in Esthetic Zone: A Case Report.

External cervical resorption (ECR) in anterior teeth poses significant treatment challenges due to esthetic and periodontal considerations. While external surgical repair demonstrates superior survival rates, internal approaches may be preferable for subcrestal lesions in the esthetic zone. This case presents a 25-year-old male with a Heithersay Class 3 and Patel 2Bp lesion. Microscope-assisted internal repair was performed using calcium hydroxide as an interim medicament, followed by mineral trioxide aggregate (MTA) restoration and root canal obturation 12 days later. Clinical and radiographic evaluations at 2, 4, and 9.5 years demonstrated complete healing, stable periodontal health, probing depths of 1-2 mm, and no signs of recurrence on cone-beam computed tomography, despite mild MTA-related crown discoloration that was acceptable to the patient. This nearly 10-year successful outcome highlights the possibility of a long-term successful internal repair with calcium hydroxide and MTA as a viable conservative option for select subcrestal ECR lesions in the esthetic zone.