Coincidence of Compound Odontoma and Cemento Ossifying Fibroma; A Rare Case Report

Objective: Cemento-ossifying fibroma defines as a relative rare osteogenic neoplasm of the jaw. This tumor includes fibrous and osseous components. Odontoma is the most common odontogenic tumor containing enamel ,dentin ,cementum and pulp tissue. in this paper we report a  rare case of ossifying fibroma associated with compound odontoma in the mandible. Case: A 37-years-old woman was referred to Oral Medicine department , Shahid Beheshti Dental School with complaint of swelling in the anterior part of the mandible, over 6 years period. Clinical examination revealed mandibular enlargement in right –anterior region with labial and lingual expansion and canine missing . panoramic view showed a large mixed radiolucent -  radiopaque lesion associated with impacted canine.The differential diagnosis include calcifying odontogenic cyst (COC) and cemento-ossifying fibroma(COF). Histopathologic examination established diagnosis of COF with multiple compound odontoma .Conclusion: The relationship between the occurrence of these two lesions is not clear and more studies are needed to establish the relationship between them