Abstract
Introduction: Benign fibro-osseous lesions of the jaw are often a problem in diagnosis and classification. Cemento ossifying fibroma is one of the odontogenic tumour fibro-osseous lesions originating from the periodontal ligament's remaining cells, which occurs in the jaw and is rarely found. These lesions are often clinically and radiographically similar to other fibro-osseous lesions of the jaw. This case report aims to discuss the clinical, radiological, and histopathological features of cemento-ossifying fibromas that are often confused with other fibro-osseous lesions. Case Report: A 53 years old man reported to the Department of Oral Maxillofacial Surgery, Hasan Sadikin General Hospital, with a chief complaint that had lumped in his right upper jaw. About four years ago, a 2x2x2 cm lump appeared around the right maxillary gum after trauma from brushing, the lump did not hurt, and the patient did not seek any treatment. Approximately three months ago, the lump was getting bigger without pain, uncomfortable because it filled the oral cavity with a clinical picture of a lump on the palate that does not bleed easily without pain, the colour of the lump is the same as the surrounding tissue, and there is no ulcer. At first, the patient was diagnosed with peripheral ossifying fibroma. Histopathological examination results showed cemento-ossifying fibroma. The therapy is excision. Conclusion: Cemento ossifying fibroma is fibro-osseous lesions that develop from the periodontal ligament and are composed of cementum, bone, and fibrous tissue. In this case, the result of the histopathological examination is a definitive diagnosis.

Key words: biopsy, fibro-osseous lesions, cemento-ossifying fibroma, excision