Diagnosis: Cemento-ossifying fibroma (COF)
Benign fibro-osseous lesions encompass a diverse group of entities that can be seen in the head and neck area. The nomenclature for these lesions creates a great deal of confusion. According to the second World Health Organization classification, oral and maxillofacial lesions related to bone are divided into 2 distinct categories: (1) nonneoplastic bone lesions, including fibrous dysplasia; and (2) osteogenic neoplasms.1The latter category includes cementifying fibromas and ossifying fibromas. While previously grouped separately, these lesions are now thought to represent the same tumor at the ends of a continuous spectrum. Tumors in which the main mineralized component is cementum are known as cementifying fibromas. Tumors in which the main mineralized component is bone are known as ossifying fibromas. Tumors with a mixture of mineralized components are known as COFs.
Pathology Quiz Case 1: Diagnosis. Arch Otolaryngol Head Neck Surg. 2010;136(11):1147-1148. doi:10.1001/archoto.2010.198-b