A novel approach to manage Schneiderian membrane perforation in the maxillary sinus floor augmentation: The "Sinus Pack" technique. Anatomical factors and surgical outcomes related to perforation size and handling. Part 3/3

Purpose: To highlight the different risk factors, whether surgical or anatomical, related to Schneiderian membrane perforation, while evaluating the predictability of currently available methods to manage such perforations. Methods: Charts of subjects experiencing perforation during maxillary sinus augmentation were retrospectively reviewed. Data related to possible anatomical and surgical risk factors were extracted. The correlation between membrane perforation size and anatomical risk factors (e.g., sinus septa, residual bone height and membrane thickness), surgical risk factors (satisfactory clinical management score - SCMs) and implant outcomes was statistically evaluated. Results: Nine out of 10 subjects with perforation size ≥5 mm presented a less than 1.5 mm (P= 0.011) sinus membrane thickness. About 80% of subjects with easy or fair SCMs presented a residual bone height lower than 4 mm (P= 0.02) The SCMs were significantly worse in subjects with a perforation size ≥ 5 mm (2.8 ± 1.5) compared to those with a perforation size < 5 mm (1.4 ± 0.7) (P= 0.03). Clinical significance: Techniques for the management of Schneider's membrane perforation should take into consideration anatomical and surgical risk factors, to render surgical therapies more predictable, reducing patient morbidity.