内部に洞粘膜の陥入を認めた大きな上顎洞内骨腫の1例

Abstract

Generally, intraoral osteoma frequently arises on the lingual side of the mandibular molar and maxillary hard palate. As for the radiopacity in the maxillary sinus of affected patients, aspergillosis-derived calculus, root insertion, and osteoma have been suggested. We report a case of osteoma arising in the maxillary sinus. The patient was a 55-year-old man referred to our department for detailed examination and treatment because radiopacity was noted in the left sinus on a panoramic radiograph obtained during a visit to a local dentist for dental treatment. Computed tomography revealed a walnut-sized oval radiopaque mass in the left maxillary sinus. The lesion had arisen in a pedunculated manner from the floor of the left maxillary sinus to form a cup shape. On the basis of our clinical diagnosis of osteoma in the maxillary sinus, the lesion was resected with the patient under general anesthesia. The excised specimen was a hard bone-like mass, measuring 45×40×20mm and containing maxillary sinus mucosa. Histopathological findings led to the diagnosis of osteoma with invagination of the maxillary sinus mucosa. One year after surgery, the course was favorable without recurrence. In this paper, we report our experience with this case of massive osteoma containing maxillary mucosa in the left maxillary sinus and the positive outcome, along with a discussion of related studies.