Solitary central osteoma of the jaws: a diagnostic dilemma

Osteomas are relatively rare benign osteogenic neoplasms, characterized by the proliferation of compact and/ or cancellous bone. Osteomas can develop as peripheral (periosteal) masses attached to the cortical plates or as central lesions arising from endosteal bone surfaces. Although multiple osteomas of the jaws are a hallmark of Gardner syndrome (familial adenomatous polyposis), nonsyndromic cases are typically solitary. A search of the literature identified 91 well documented cases of solitary osteoma of the jaws published since 1955: 93.4% were peripheral and only 6.6% central, a ratio of 14: 1 in favor of peripheral osteomas. Solitary central osteomas of the jaws seem to be very rare, with only 6 such cases reported since 1955. Adding the 4 new cases described here brings the total to 10 central osteomas, 30% occurring in the maxilla and 70% in the mandible. Whereas peripheral osteomas are fairly easy to diagnose, central osteomas pose a more challenging diagnostic problem and need to be differentiated from other similar lesions of the jaws, such as central ossifying fibroma, condensing osteitis, idiopathic osteosclerosis, osteoblastoma, cementoblastoma, and complex odontoma. With such a low number of cases of central osteoma reported, the objectives of the present report are to describe 4 new cases, analyze the clinical and radiographic characteristics, and discuss the features which distinguish these lesions from other similar lesions of the jaws.