Postoperative maxillary cyst.

The postoperative maxillary cyst develops in the maxillary sinus between the ages of 30 and 40 in persons who received sinus surgery 10 to 20 years earlier. Etiology of the cystic lesion appears to be derived from the infected sinus mucosa left after a sinus operation. Chief complaints of postoperative maxillary cysts are swelling or pain in the buccal region, discomfort of the maxilla or maxillary teeth and exophthalmos. Characteristic panoramic radiographic findings of the postoperative maxillary cyst are a monolocular cystic radiolucency with a well-defined margin and surrounding sclerotic bone in the floor of the maxillary sinus.