Oral focal mucinosis (OFM) is a rare soft tissue lesion of unknown aetiology. Clinically, it is most commonly found on the gingiva and presents as a painless, sessile or pedunculated mass. Histologically, it is characterized by focal myxoid degeneration of underlying connective tissue. Fifty-three-year-old patient reported with a painless, firm and fibrous gingival overgrowth present from 7 to 8 months. Clinical examination and patient's history pointed towards "irritation fibroma". An excisional biopsy was performed. The histopathologic diagnosis was established as OFM, an uncommon and poorly characterized type of lesion. This case report stresses on the fact that prediagnosis of OFM is almost impossible. Thus though rare, OFM must be considered in the differential diagnosis of soft tissue overgrowths in oral cavity.
Keywords: Alcian blue; biopsy; gingival overgrowth.