We reported a rare case of cemento-ossifying fibroma on the right jaw of an elderly person. A 66-year-old woman complained of gingival swelling in the right first and second small molar region. Radiographic examinations demonstrated a relatively well-demarcated radiolucent lesion that was continuous with the roots of the teeth and, contained small radiopaque spots. We enucleated the lesion under general anesthesia, and the final diagnosis was cemento-ossifying fibroma. We further discuss the mechanism underlying the development of this tumor in an elderly person
