Does sinus floor elevation in the presence of Schneiderian membrane pathology increase therisk of membrane perforation and implant failure rate?

Schneiderian membrane (SM) thickness >2mm is regarded to be a pathological mucosal change. The aim of the current study is to answer the question” Does presence of pathological changes in the SM increase the risk of sinus perforation during surgical sinus floor elevation (SFE)?” An electronic database (PubMed, Embase, Cochrane Library, and Chinese database) were systemically searched for the studies published until February 2020. Randomized and non-randomized studies that reported the incidence of SM perforation in patients with SM pathology (antral pseudocyst or mucosal thickening) during SFE. The outcome measures were the incidence of SM perforation and implant survival rate. The pooled odds ratio (OR) with 95% confidence intervals and the Fixed-effects model were calculated. P-value ≤ 0.05 was considered to be statistically significant. Eighteen studies with a total of 1542 patients and 1797 SFE were included. Statistically insignificant difference in the incidence of SM perforation was observed between the normal-appearing sinus and thickened sinus mucosa (Fixed; OR, 0.896; 95%CI, 0.504 - 1.59; P =0.707, I 2 =32%). The rate of SM perforation in the normal sinus, mucosal thickening, and antral pseudocysts was 14%, 6%, and 6% respectively. The Implant survival rate was 98% in the normal sinus, and 100% in antral pseudocyst and mucosal thickening. SM thickening or antral pseudocyst did not increase the risk of membrane perforation and implant failure rates. Future RCTs are needed to evaluate the risk of the presence of pathological changes in the SM on the failure of the bone augmentation and dental implant.