Cementoblastoma Radiograph — MFDS Part 1 MCQ

Instant feedback + full explanation. One question, done properly.

ModerateRadiologyCementoblastoma RadiographMFDS Part 1

A periapical radiograph of a vital mandibular premolar shows a well-defined, round radiopaque mass fused to the root. The normal root outline is obscured, and the mass is surrounded by a thin radiolucent rim. What is the most likely diagnosis?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: B — Cementoblastoma

The correct answer is B, cementoblastoma. Its characteristic radiographic appearance is a well-circumscribed radiopaque or mixed-density mass fused to a tooth root, with obscuration of the normal root outline and a surrounding radiolucent rim. The associated tooth is commonly vital, and the mandibular premolar–molar region is a typical site. Hypercementosis enlarges the root while preserving its outline, periodontal ligament space and lamina dura around the altered root. Periapical cemento-osseous dysplasia is not fused to the root and commonly affects multiple mandibular anterior teeth. An odontoma is a tooth-like or irregular calcified odontogenic mass, often associated with failure of eruption. An osteoma arises from bone and is not characteristically fused to a tooth root.

Reference: Ide F, et al. The True History of Cementoblastoma. Head and Neck Pathology. 2023. https://pubmed.ncbi.nlm.nih.gov/36723849/