Risk Factors of Membrane Perforation and Postoperative Complications in Sinus Floor Elevation Surgery: Review of 407 Augmentation Procedures

To test patient- and sinus-related risk factors for an association with intraoperative membrane perforation and postoperative complications after sinus floor augmentation surgery.Sinus floor elevation procedures using a lateral approach were retrospectively analyzed for patients' medical history and sinus anatomy on computed tomographic scans. Complications per sinus after membrane elevation and augmentation using a mixture of autologous bone and deproteinized bovine bone substitute (Bio-Oss) were recorded. Logic regression (adjusted using the generalized estimation equation approach) was performed to analyze the influence of patient age, gender, smoking habits, sinus septa, residual bone height, and mesiodistal elevation width.Of 407 sinus grafts in 300 patients (mean age, 56 yr), perforation of the Schneiderian membrane occurred in 35 sinuses (8.6%) and was significantly associated to the presence of sinus septa (odds ratio [OR] = 4.8; P = .002) and decreased residual bone height (OR = 0.01; P.001). Smoking increased the risk of membrane perforation (OR = 4.8; P = .002), sinusitis (OR = 12.3; P.001), and wound dehiscence (OR = 16.1; P = .005). Cases of sinus membrane perforation had higher odds for postoperative sinusitis (OR = 10.5; P.001). The probability of wound dehiscence increased with the size of the elevated area (OR = 3; P.001).The results of the study suggest that the presence of sinus septa and residual bone height less than 3.5 mm are the main risk factors increasing sinus membrane perforation rates. There was a higher prevalence for sinusitis in cases of membrane perforation (31.4%) despite intraoperative closure with resorbable membranes (Bio-Guide). Smokers generally exhibited greater chances for complications.