Focal cemento-osseous dysplasia of the mandible: a diagnostic approach using Modified Gallego staining—A case report

Abstract

Focal cemento-osseous dysplasia (FCOD) is a reactive or dysplastic lesion within the spectrum of fibro-osseous lesions (FOLs). It is typically asymptomatic, and most cases are identified incidentally on radiographic examination. This case highlights the diagnostic utility of the Modified Gallego stain (MGS) in evaluating mandibular FCOD. A 33-year-old woman presented with a painless swelling of recent onset involving the left mandibular region. Radiographic examination revealed a well-defined, corticated, mixed-density lesion in the premolar region, located apical to the teeth and near the mandibular canal, with extension toward the inferior border of the mandible. Histopathological examination of hematoxylin and eosin-stained sections demonstrated both fibrous and osseous components. MGS was subsequently performed to characterize the mineralized component further and distinguish cementoid tissue from osteoid, confirming the presence of cementoid material. Although FCOD is generally clinically silent, the lesion’s proximity to the mandibular nerve and extension toward the inferior border of the mandible may predispose to complications such as paraesthesia and facial asymmetry if left untreated. This case emphasizes the importance of timely, accurate diagnosis and demonstrates the potential value of MGS as an adjunctive histopathological stain in diagnosing mandibular FCOD.