Clinical Study on the Use of Symbios Xenograft for Sinus Floor Elevation

The study aims to evaluate the clinical and radiological behavior, the histological and morphometrical components, the expression of proteins related to bone formation, and the analysis of markers of reparative mesenchymal stromal cells, after using two different xenogenic biomaterials in combination with autogenous cortical bone for maxillary sinus floor elevation. A randomized split-mouth clinical study is designed to include patients in need of two-stage bilateral maxillary sinus floor elevation. Patients will be assigned to receive a mix of autogenous cortical bone (collected by a bone scraper from the access window to the maxillary sinus) and anorganic bovine bone (BioOss Xenograft) in one maxillary sinus or autogenous cortical bone and porcine bone mineral (Symbios Xenograft) in the other maxillary sinus. Cone-beam computerized tomography (CBCT) scans will be performed before and after sinus floor elevation and 6, 12 and 18 months after the procedure to assess the bone gain. Bone core biopsies will be obtained at the site of implant placement 6 months after the floor elevation. Histological sections will be subjected to histomorphometric and immunohistochemical evaluation of differentiation markers.