Lateral sinus floor elevation in patients with sinus floor defects: A retrospective study with a 1- to 9-year follow-up.

Objectives: We aimed to retrospectively evaluate the long-term clinical outcomes of lateral sinus floor elevation (LSFE) in patients with sinus floor defects.

Materials And Methods: Between 2008 and 2020, patients with sinus floor defects were recruited after confirmation on preoperative cone-beam computed tomography (CBCT). The split-thickness flap technique with a palatal crestal incision was used to manage tissue adhesion in the bone defects area. A resorbable collagen membrane was used to close the sinus floor defects from the crestal side before bone substitute placement. Of 58 implants, 47 (81.0%) were placed after an 8-month healing period, whereas 11 were placed simultaneously. Patients were followed up by radiography and clinical examination for 1-9 years. Finally, the cumulative survival rate (CSR) of implants, surgical complications, and marginal bone loss (MBL) were recorded and analyzed.

Results: In total, LSFE was performed in 36 sinuses (35 patients) with sinus floor defects, of which surgery was completed in 35 sinuses (97.2%) in the first attempt. Schneiderian membrane perforations (SMP) occurred in 10/36 (27.8%) sinuses; nine were repaired carefully, whereas one surgery was suspended due to complicated SMP, and successful re-entry LSFE was performed 4 months later. After a follow-up period of 1-9 years, the CSR was 96.5% at the 1-year, 3-year, 5-year, and 7-year follow-ups and 64.3% at the 8-year follow-up.

Conclusion: Within the limitations of this study, sinus floor defects seem not to compromise LSFE therapy after appropriate management and long-term clinical outcomes are predictable.