Peripheral presentation of fibrous dysplasia in the posterior mandibular gingiva: A rare case report

Fibrous dysplasia is a benign fibro-osseous developmental disorder that commonly presents as an intraosseous lesion causing gradual expansion of the craniofacial bones; however, an entirely peripheral soft-tissue presentation is exceptionally rare. To the best of our knowledge, this report describes the first documented case of peripheral fibrous dysplasia presenting as a localized, exophytic gingival mass in the posterior mandible. A 30-year-old female presented with a firm, exophytic soft-tissue lesion located in the left posterior mandibular gingiva. The lesion had been present for approximately one month and was initially misdiagnosed and treated as a dental abscess before specialist referral. Clinical, radiographic, and histopathological examinations were performed. Histopathological analysis demonstrated irregular, curvilinear osseous trabeculae embedded within an inflamed fibrous connective tissue stroma with a complete absence of peripheral osteoblastic rimming or malignancy, confirming the diagnosis of peripheral fibrous dysplasia. The lesion was successfully managed via complete surgical excision with safety margins along with the extraction of the involved adjacent teeth. The postoperative healing course was completely uneventful, demonstrating excellent local tissue recovery and no clinical or radiographic signs of recurrence. This case highlights the vital clinical importance of considering peripheral fibrous dysplasia in the differential diagnosis of exophytic gingival fibro-osseous lesions to ensure accurate diagnosis and appropriate definitive surgical management.