Aim: To report the use of cone beam computed tomography in the assessment of external cervical resorption lesions.
Summary: Asymptomatic external cervical resorption lesions were diagnosed radiographically in two patients. Clinical examination in both cases was unremarkable. Cone beam computed tomography scans revealed the true nature of the lesions in three dimensions. The resorption lesion in case 1 was confined predominantly to the buccal aspect of the root, the lesion had not perforated into the root canal. A mucoperiosteal flap was raised to gain access to the lesion, the resorptive lesion was excavated and the defect repaired with glass ionomer cement. In case 2 the cone beam computed tomography scan revealed that the resorptive lesion was more extensive than it appeared radiographically, making the prognosis of reparative treatment very poor. In this case, the patient was advised to have the tooth extracted.
Key learning points: The true extent of external cervical resorption lesions cannot always be estimated from conventional radiographs. Cone beam computed tomography can be a useful diagnostic tool in the management of external cervical resorption lesions.