External cervical resorption — ORE Part 1 MCQ

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HardRestorative DentistryExternal cervical resorptionORE Part 1

A 37-year-old patient who had orthodontic treatment as a teenager presents with a pinkish cervical discolouration on an upper canine. The tooth responds normally to sensibility testing, periodontal probing is normal, and a periapical radiograph shows an irregular cervical radiolucency superimposed over the canal outline. What is the most appropriate investigation?

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Correct answer: A — Cone beam CT for three-dimensional assessment

Explanation lettering: B = shown as A · A = shown as B · E = shown as C · C = shown as E

This clinical presentation is highly consistent with external cervical resorption (ECR): pinkish cervical discolouration (vascular granulation tissue), normal pulp vitality, and cervical radiolucency on periapical radiography in a patient with orthodontic history. Although the periapical radiograph demonstrates the lesion, it is insufficient for diagnosis and management. CBCT is the gold-standard investigation because it uniquely provides three-dimensional assessment of lesion depth, circumferential spread, proximity to the canal, and stage of progression—information that directly determines treatment planning and prognosis. Multiple comparative studies demonstrate CBCT sensitivity significantly exceeds that of intraoral radiographs alone, and treatment plans change in the majority of cases when CBCT is reviewed. Option A (bitewing) adds no diagnostic value beyond periapical imaging. Option C (contralateral EPT) is irrelevant; the affected tooth is already vitally responsive. Options D and E are anatomically unrelated to the maxillary canine lesion.

Reference: Patel et al. (2021). External cervical resorption: Radiological diagnosis and literature. PubMed PMID: 34434279. Supporting comparative studies: Goodell et al. (2017) and Vaz de Souza et al. (2017) on diagnostic efficacy; and multiple prospective studies (2021–2022) on clinical decision-making impact. https://pubmed.ncbi.nlm.nih.gov/34448951/