A 1222-year-old Turkish man was seen at the Dental Clinic on August 5, 1995 for evaluation of a painless, slowly enlarging, swelling of the left facial region of 5 years in duration (Fig 1). There were no significant findings in the medical or dental history and no history of trauma to the region. Palpation revealed a firm, slightly tender, well-circumscribed, mobile mass approximately 5 3 3 cm, covered by normal skin and apparently not attached to the underlying bone. The serum levels of calcium, calcitonin, and parathyroid hormone were all within normal range. Results of hematologic and urine analyses were also unremarkable. Radiographs revealed several well-circumscribed, radiopaque, spheric masses in the soft tissues of the left face; these did not appear to be attached to the mandible or maxilla (Figs 2, 3). Both T1and T2-weighted magnetic resonance images (MRI) were obtained to evaluate the vascularity of the lesion. These images also revealed the well-circumscribed, spheric osseous masses (Fig 4A), surrounded by hemorrhagic areas (Fig 4B). The lesion in aggregate was located entirely within the left masseter muscle. The preoperative clinical impression was that the lesions represented a benign osseous process, possibly teratomas, osteomas, calcified lymph nodes, osseous hamartomas, or calcified hematomas. The masses were surgically excised under general anesthesia through an extraoral approach (Fig 5), and the specimens were sent for microscopic examination. GROSS FINDINGS