Maxillary sinus augmentation via the bone lid technique: A prospective, radiographic case series.

BACKGROUND Maxillary sinus augmentation is one of the most performed procedures to increase the bone quantity of the atrophic maxilla to allow implant placement. The aim of the present case series was to describe a surgical protocol to perform maxillary sinus augmentation with the "bone lid technique," and its outcomes in a cohort of patients eligible for the procedure. METHODS After the initial clinical evaluation, a cone-beam computed tomography (CBCT) examination was performed for preoperative assessment. Patients were then scheduled for surgical intervention. At 6-9 months follow-up, patients underwent a second CBCT scan to evaluate bone height following bone graft and to schedule implant placement. RESULTS A total of 11 patients were enrolled in the study with a total of 13 sinus lift procedures. Membrane perforation was registered in 4 cases (30.76%). Mean surgical time was 67.69 min (SD 6.51). Postoperative period was uneventful in all patients, in the absence of complications. The mean graft volume increase was 2.46 cm3 (SD 0.85), and the mean height increase was 14.27 mm (SD 3.18). Mean membrane thickness was 1.40 mm (SD 0.75). In all the 4 cases with sinus membrane perforation, the membrane had a thickness lower than 1 mm. CONCLUSIONS The present study highlights that the maxillary sinus augmentation with bone lid repositioning could provide repeatable results in terms of bone height increase. The technique appears reliable both in terms of bone gain and absence of complications. KEY POINTS The bone lid technique for maxillary sinus augmentation provides repeatable results in terms of bone height increase. The favorable clinical outcomes can be related to an enhancement of bone formation due to the unique osteoconductive and osteoinductive properties of autogenous bone, along with a reduction of soft tissue ingrowth. Complications were not observed in any of the patients following the surgical procedures. The risk of Schneiderian membrane perforation is inversely proportional to membrane thickness; the thinner the membrane is, the higher the risk to perforate it.