LAUSR

BACKGROUND Lateral- window sinus floor elevation (LSFE) is a reliable procedure to reconstruct the posterior maxilla for implant therapy. This retrospective study aimed to investigate risk factors associated with Schneiderian membrane perforation (SMP) occurrence during lateral-window sinus floor elevation (LSFE) and longitudinal regenerative outcomes following LSFE up to 9 years. MATERIALS AND METHODS Patients who had LSFE between 2010-2019 were included. All demographic and surgical-related data were retrieved from existing electronic health records. Radiographs were used to evaluate the vertical dimensional changes of ridge and graft materials and the potential anatomic factors of SMP. RESULTS 122 LSFE procedures in 99 patients were included in the study. Mean ridge height gain and graft shrinkages were 9.5±3.47 and 1.57±2.85 mm. The influence of the healing period on graft shrinkage showed a positive trend; the longer the healing period, the greater the graft shrinkage (p = 0.09). The pathology in the sinus showed a positive correlation with SMP (p = 0.07). However, other anatomical factors did not negatively impact SMP and subsequent ridge height gain (p>0.05). CONCLUSION With inherent limitation, the findings with up to 9 years of follow-up indicate a consistent ridge remodeling lasting for about three years after LSFE procedures. SMP or membrane thickening may not significantly affect the ridge gain following LSFE. The healing period had the most significant influence on graft shrinkage, showing that the longer the healing time between LSFE and implant placement, the greater the graft shrinkage. This article is protected by copyright. All rights reserved.