The influence of different forms of sinus membrane perforation on the prevalence of postoperative complications in lateral window sinus floor elevation: A retrospective study

Background Maxillary sinus membrane perforation (SMP) during lateral window sinus floor elevation (SFE) might be associated with postoperative complications (PC). Objectives To evaluate the prevalence of PC and clinical implant outcome for different forms of SMP with lateral window SFE. Material and Methods The prevalence of PC such as maxillary sinusitis, graft necrosis and wound infection was retrospectively evaluated for 434 lateral window SFE (334 patients) with 331 SFE (241 patients) without and 103 SFE (93 patients) with SMP. SMP was additionally classified into four subgroups regarding to membrane perforation size (small-moderate [10 mm]) and membrane biotype ([BT] thin vs. thick). Additionally, patient- and surgery-related risk factors affecting PC and the 1-year implant survival rate were evaluated for SFE without and with SMP and subgroups. Results A significantly higher prevalence including significant odds ratios of PC such as maxillary sinusitis (10/103 [9.7%] vs. 4/331 [1.2%]; p < 0.021; OR: 8.85; p < 0.021) and graft necrosis (7/103[6.8%] vs. 1/103[0.3%]; p < 0.017; OR:7.43; p < 0.017) was found for SFE with than without SMP. The SMP subgroup with large size and thin BT involved significantly (p < 0.005) more PC (15/20[75%]) than all other SMP subgroups (5/20[25%]). For the risk factors evaluated the univariate analysis demonstrated differences of PC for the presence versus absence of SMP (p < 0.001) and for thin versus thick sinus mucosa (p < 0.038; p < 0.006) but not for sex, smoking, sinus septa and surgical stage. In the multivariate risk factors analysis, PC were significantly related to risk factors such as large size with thin BT (OR:18.049; p < 0.007). The 1-year implant survival rate did not differ between SFE without (99.5%) and with SMP (99.1%), regardless of successfully repaired subtype of SMP. Conclusion The synopsis of perforation size and membrane biotype is crucial in differentiating different forms of SMP assessing and anticipating different prevalences of PC in lateral window SFE.

Automated summary

Maxillary sinus membrane perforation during lateral window sinus floor elevation may be associated with increased risk of postoperative complications, particularly when perforation size is large and membrane biotype is thin. However, the 1-year implant survival rate does not significantly differ between cases without SMP and those with successfully repaired SMP.