Prescence and Distribution of Intrasinusal Septa in the Maxillary Sinus Floor

The loss of upper teeth causes alveolar process resorption and maxilary sinus pneumatization. Oral implantology has solved these losses, however, when pneumatization of the maxillary sinus exists, bone availability is diminished, difficulting implantology procedure. To remedy this situation, the surgical technique of lifting the maxillary sinus floor is indicated, which can have complications because of the internal maxillary sinus morphology, specifically the presence of intrasinusal septa. The aim of this study is to verify the presence and distribution of intrasinusal septa, due to its importance in surgical techniques performed in oral implantology. We conducted a descriptive study, based on visual analysis of isolated maxilary bones. Of 65 bones, 51 (42 dentate and 9 edentulous)were selected that met certain inclusion criteria. The second part of the study was, to divide the sinus floor topographically into three regions: anterior to the zygomatic alveolar crest, in relation to it, and posterior to the crest. The observation of the septa was performed by a single examiner, assisted by a USB device with 4 high-luminance LEDs. Of the 51 maxillary analyzed obtained: 74.5% had at least one intrasinusal septum, 25.4% showed no visible septa. The maxilary bones that had a single septum corresponded to 33.3% of the sample, 19.6% of the sample had only two septa, 15.7% had three septa, while the maxillary bones that had more than three intrasinusal septa corresponded only to 5.9%. Of all septa found (75 septa) 42% was observed in the anterior region, 21% in the region of the zygomatic crest and 37% in the posterior region of the maxillary sinus. Of the 42 dentate maxillary bones in 88,1% present intrasinusal septa, while the total edentulous maxillary bones (9) only 11% present intrasinusal septa. This study establishes that a significant portion of the maxillary bones have intrasinusal septa that modify the morphology of the sinus floor with a variable frequency and location. This situation must be considered and evaluated by imaging techniques in case of performing surgical elevation of the maxillary sinus floor.