摘要
BACKGROUND Ossifying fibroma is a type of benign fibro-osseous lesion.Most lesions affect the mandible region,particularly the molar and pre-molar areas.It predominantly affects females between the second to fourth decades of life.Larger ossifying fibroma tumors require more extensive resection.CASE SUMMARY A 39-year-old female complained of occasional pain and tumor enlargement on her left jaw for the 3 years prior to presentation.Intraoral examination revealed a firm swelling on her left lower gum.Extraoral examination revealed swelling on the left mandible body with no erythema and superficial ulcer.Computed tomography scan revealed a circular-shaped lesion on the patient’s left mandible body with a well-defined radiolucent border,sized 3.2 cm×2.8 cm×0.9 cm.The tumor was removed by marginal mandibulectomy.Biopsy from the resected tumor suggested cemento-ossifying fibroma(COF).CONCLUSION COF is often unnoticed,but this slow-growing tumor can cause significant symptoms regarding its distortion into adjacent structures.