Perforation of the maxillary sinus membrane during sinus lift: a retrospective study of the frequency and possible risk factors
Visiting Specialist of the Department of Maxillofacial Surgery and Surgical Dentistry, Faculty of Dentistry, University of Bern (Bern, Switzerland); implantology program instructor of San Sebastian University (Santiago, Chile).
Purpose: To analyze the frequency of perforation of the sinus membrane during maxillary sinus floor elevation (SFE) and to assess possible risk factors.
Materials and Methods: Seventy-seven cases of SFE performed with a lateral window approach were evaluated retrospectively. Clinical and radiographic variables potentially influencing the risk of sinus membrane perforation were evaluated and divided into patient-related factors (age, sex, smoking habit); surgeryrelated factors (type of surgical approach, side, units, sites, and technique of osteotomy); and maxillary sinus–related factors (presence and height of septum, height of residual ridge, thickness of lateral sinus wall, width of antrum, and thickness and status of sinus membrane).
Results: The following factors presented with at least a 10 % difference in rates of perforations: smokers (46.2 %) versus nonsmokers (23.4 %), simultaneous (32 %) versus staged (18.5 %) approach, mixed premolar-molar sites (41.2 %) versus premolar-only sites (16.7 %) versus molar-only sites (26.2 %), presence of septa (42.9 %) versus no septa (23.8 %), and minimum height of residual ridge ≤ 4 mm (34.2 %) versus > 4 mm (20.5 %). These same parameters, except minimum height of residual ridge, also showed an odds ratio above 2. However, none of the comparisons reached statistical significance.
Conclusion: The present study failed to demonstrate any factor that statistically significantly increased the risk of sinus membrane perforation during SFE using the lateral window approach.