Non-Interventional Resolution of External Cervical Root Resorption: A Case Report

External cervical resorption (ECR) is an uncommon, often asymptomatic condition that originates below the epithelial attachment. Orthodontic treatment is recognised as a common predisposing factor. This report describes a 24-year-old female with a mandibular second molar (Tooth 37) previously diagnosed with Heithersay Class 3 ECR. The lesion was initially deemed untreatable and managed conservatively with long-term monitoring. After 8 years, radiographic imaging demonstrated apparent hard-tissue deposition and lesion regression. Clinical and radiographic assessments confirmed normal pulp vitality, absence of periapical pathology, and no symptoms. Radiographic evaluation also identified an additional ECR lesion affecting the maxillary first molar (Tooth 26), highlighting the diagnostic value of thorough imaging in ECR cases. This case suggests that even advanced ECR lesions may stabilise in the absence of ongoing resorptive stimuli, supporting a cautious and individualised approach to ECR management.