Maxillary sinus augmentation following removal of a maxillary sinus pseudocyst after a shortened healing period

Dome-shaped radiopacities on the floor of the maxillary sinus are commonly interpreted as a sinus cyst on radiographs during dental implant planning. They might present an obstacle in sinus grafting, leading to bone graft failure or implant loss later. The therapeutic approaches to the removal of such cystic lesions and the following sinus augmentation are still controversial. The purpose of this article is to present a modified technique that can be used for predictable removal of a maxillary sinus cyst and sinus augmentation after a shortened healing period in patients with maxillary sinus pseudocysts.

A total of 11 patients with a mean age of 43.7 years with a radiographic dome-shaped opacity in the posterior maxilla sinus were included in this study. A lateral sinus window (with a diameter of about 5 mm) was prepared, and removal of the cyst was performed with grasping forceps. Three months after removal of the cyst, a conventional sinus augmentation with xenogeneic material was undertaken. Dental implants were placed 6 months later. Panoramic radiography and coronal/axial computed tomography were performed to diagnose the sinus lesion preoperatively and for follow-up.

A total of 11 pseudocysts were removed from the sinuses of 11 patients under local anesthesia. Histologic evaluation showed antral pseudocysts in all specimens. A soft tissue scar was evident after 3 months of healing at the time of sinus augmentation. No sinus membrane perforation was seen or occurred during the sinus augmentation. A total of 17 implants were placed and restored prosthetically. No clinical complications were observed. The patients were followed up for a mean of 29.2 months (range, 17-43 months) after prosthetic loading, during which no implants were lost and no recurrence of the antral pseudocyst was observed.

The described modified surgical technique allows the minimally invasive removal of the antral pseudocyst and histologic verification of the diagnosis without compromising the nasoantral entrance as well as the anatomy of the sinus for future sinus augmentations. It can be performed under local anesthesia without endoscopic equipment while shortening the treatment period.