Work

Prevalence, Risk Factors, and Outcomes of Radiographically Detected Void Formation Following Lateral Sinus Floor Elevation: A Retrospective Study

Year: 2026

Type: article

Abstract: OBJECTIVES: To investigate the prevalence, risk factors, and impact of void formation within graft materials following lateral sinus floor elevation (LSFE) on long-term implant survival. MATERIALS AND METHODS: This retrospective study analyzed 307 patients who underwent LSFE between 2018 and 2023. Voids were identified on 6-month postoperative cone-beam computed tomography (CBCT), and patient-, anatomical-, and surgery-related variables were assessed. Least Absolute Shrinkage and Selection Operator (LASSO) regression and multivariable logistic regression were used to identify independent risk factors. Implant survival in void versus non-void groups was compared using Kaplan-Meier analysis and the log-rank test. RESULTS: Voids were detected in 31.3% of cases (96/307). Three independent risk factors were identified: a specific graft material (OR = 4.02, 95% CI: 1.73-9.33, p = 0.001), increased graft amount (OR = 2.20, 95% CI: 1.20-4.01, p = 0.011), and a smaller sinus mucosa tension angle (SMTA; OR = 0.98, 95% CI: 0.96-1.00, p = 0.027). In a sensitivity analysis confined to conventional graft materials, graft material amount remained robust (OR = 2.02, p = 0.025), with Stage III periodontitis, multiple-tooth units, and endo-sinus bone gain additionally identified, whereas membrane perforation was unexpectedly protective (OR = 0.30, p = 0.049). Over a mean 46.6-month follow-up, voids were significantly associated with a higher implant failure rate (7.3% vs. 1.9%) and reduced cumulative survival (p = 0.014). CONCLUSIONS: Radiographically detected voids following LSFE are associated with increased implant failure and lower cumulative survival. Void formation was independently associated with graft composition, graft material amount, and SMTA; the association with graft material amount persisted after excluding one specific material. Membrane perforation showed an unexpected protective association requiring prospective validation.

Source: Clinical Oral Implants Research

DOI: 10.1111/clr.70197