OBJECTIVES: Osseous dysplasias are the most common subtype of fibro-osseous lesions of the maxillofacial bones. They are benign and often present as incidental asymptomatic lesions. Diagnosis can be made with clinical and radiographic examination. CASE REPORT: This article reports the case of a 47-year-old man with a huge cementifying osseous dysplasia of the maxilla that presented with secondary infection after teeth extraction and repair of oroantral fistula. A subtotal maxillectomy had to be done after conservative treatment failed to resolve the infection. DISCUSSION/CONCLUSION: Biopsy, tooth extraction or surgical trauma to the affected bones of osseous dysplasia could easily lead to severe secondary infection, the treatment of which may be very difficult, and thus should be avoided if possible. and S. Akbulut, M. G. Demir, K. Basak, M. Paksoy