Midline Mandibular Lesion — ORE Part 1 MCQ

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HardOral PathologyMidline Mandibular LesionORE Part 1

A 50-year-old patient has a slowly enlarging, well-defined multilocular radiolucency in the anterior mandible. It extends from the left first premolar to the right first premolar and crosses the midline. The adjacent teeth are displaced but respond normally to sensibility testing. Which diagnosis is most likely?

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Correct answer: C — Ameloblastoma

The best answer is **ameloblastoma**. The important pattern is a slowly enlarging, multilocular anterior mandibular radiolucency that crosses the midline and displaces teeth that remain vital. Ameloblastoma is a locally aggressive odontogenic tumour and can produce this expansive, tooth-displacing appearance. A periapical granuloma requires pulpal infection and is therefore associated with a non-vital tooth. A residual cyst occurs at a previous extraction site. A lateral periodontal cyst is usually a small, well-circumscribed lesion on the lateral root surface, rather than a large midline-crossing lesion. A nasopalatine duct cyst occurs in the anterior maxilla, not the mandible. Odontogenic keratocyst can cross the midline but is more often posterior mandibular and is not available as an option.

Reference: Martins et al. Ameloblastomas mimicking apical periodontitis: a case series. International Endodontic Journal, 2022. https://pubmed.ncbi.nlm.nih.gov/35660730/