An osteoi osteoma is a benign tumor which arises from osteoblasts and originally thought to be a smaller version of an osteoblastoma. Characterized by less than 1.5cm diameter, osteoid osteomas most frequently occur in males in the vertebrae or in the long bones and less commonly in the mandible or other craniofacial bones. Severe pain typically occurs at night and may be relieved by aspirin or other nonsteroidal antiinflammatory drugs.