Cemento-ossifying fibroma is a benign fibrous lesion with an unknown cause, mostly asymptomatic, painless swelling of the affected jaw. This is a case report on a cystic lesion found on radiographic examination in a patient with an extraction of mandibular left tooth. A 29-year-old female was referred to Pusan National University Dental Hospital due to a radiopaque lesion in the left mandible. On the medical history examination, the left lower mandibular tooth had been extracted 4 years ago, and there were no specific findings in the general medical history. According to histopathologic findings, along with proliferation of spindle cells, cementum-like substances were observed along with irregularly shaped osseous calcified substances containing osteocytes in the cellular fibrous connective tissue. In this study, we report a case that showed cystic changes due to tooth extraction, which made it complicated to determine the differential diagnosis from the existing fibrous-osseous lesion.

• 전민아(부산대학교 치의학전문대학원 구강악안면외과학) | Min-A Jeon (Department of oral and Maxillofacial surgery, School of dentistry, Pusan National University)
• 하규봉(부산대학교 치의학전문대학원 구강악안면외과학) | Gyu-Bong Ha (Department of oral and Maxillofacial surgery, School of dentistry, Pusan National University)
• 유미현(부산대학교 치의학전문대학원 구강병리학 교실/치의생명과학연구소) | Mi-Heon Ryu (Department of oral pathology, School of dentistry, Pusan National University/Dental and life Science Institute, Pusan National University)
• 황대석(부산대학교 치의학전문대학원 구강악안면외과학 교실/치의생명과학연구소) | Dae-seok Hwang (Department of oral and Maxillofacial surgery, School of dentistry, Pusan National University/Dental and life Science Institute, Pusan National University) Correspondence