Complications during augmentation in maxillary sinuses associated with interfering septa

Objective: This retrospective chart review assessed the prevalence and severity of sinus membrane tear complications as they related to the presence of sinus septa. Methods: The study included 67 patients treated at two private periodontal practices. 79 sinus lifts were performed by one operator (T.I.), a periodontist. 107 implants were placed. The effect of patient-, implant design-, bone graft-, implant placement timing-, and intrasurgical-related risk factors on implant survival, marginal bone loss, sinus membrane tears, major postoperative complications, and operating time were evaluated. Preoperative Cone Beam Computed Tomography (CBCT) images were evaluated using Kodak 3D Imaging v2.4 software and the distribution of interfering septa according to Class I (buccal-lingual direction), Class II (mesial- distal direction), Class III (horizontal orientation), and Class IV (combinations of Class I, II, or III) was assessed. Radiographic measurements of marginal bone loss (mm) were made using Image J v1.46 software. Results: Interfering septa were identified in 48.1% of sinuses. Of sinuses with septa, 71.1% of these contained a Class I septum. The overall implant survival rate was 100%. Patient-related risk factors were not found to be significantly associated with marginal bone loss, the occurrence of sinus membrane tears, or any major postoperative complications. Non-platform-shifted implants were found to be significantly associated with increased marginal bone loss (P<0.001). Sinus membrane tears were not found to be associated with either major postoperative complications or increased marginal bone loss. The presence of a septum on the pre-operative CBCT scan was found to be significantly associated with the occurrence of a sinus membrane tear (P