{Reference Type}: Case Reports {Title}: Large cemento-ossifying fibroma of the mandible involving the infratemporal and parapharyngeal spaces. {Author}: Guddadararangiah S;Ram Shetty S;Al-Bayatti S;Narasimhan S; {Journal}: Heliyon {Volume}: 7 {Issue}: 7 {Year}: Jul 2021 {Factor}: 3.776 {DOI}: 10.1016/j.heliyon.2021.e07594 {Abstract}: Cemento-ossifying fibroma is a benign fibro-osseous lesion of the jaws. Cemento-ossifying fibroma develops from the periodontal ligament and contains multipotent stem cells that can form cementum, lamellar bone, and/or fibrous tissue. These tumours occur in the third and fourth decades of life with higher predilection of occurrence in the female population and seldom attain a large size. We report a rare case of cemento-ossifying fibroma in a 45-year-old man involving the body of the mandible and extending into the para-pharyngeal and infratemporal region. This article describes the clinical, radiographic, and histological features of a large cemento-ossifying fibroma of the mandible.