Background: Reconstruction of the edentulous upper maxilla is one of the most complex challenges in implantology, not only for the poor quality of the bone presents in this region but correspondingly there is maxillary sinus pneumatization which occurs after dental extraction.Methods: In this study a total of four patients with bilateral partial or complete edentulous posterior maxilla with pneumatized maxillary sinuses (eight maxillary sinuses) with a residual alveolar bone ≤ 5 mm, and indicated for bilateral maxillary sinuses lifting through the lateral window approach with simultaneous implants, the eight sinuses were classified into two equal groups (split mouth), Group A (control group): involve four sinuses grafted with intra oral autogenous bone graft (symphysial region), Group B (study group): involve four sinuses grafted by synthetic β Tri-Calcium Phosphate In Calcium Sulphate Matrix bone graft (geneX TM).Results: At the 6 months postoperative CBCT, in radiodensometric analysis; the mean bone density readings of the control group showed statistical significant higher value than the study group, while in volumetric analysis; There was a statistical significant decrease in control group bone graft volume and statistical significant increase in study group bone graft volume.Conclusions: (Beta tri calcium phosphate / calcium sulphate) as a synthetic bone graft is capable to form a bone with good quality and quantity, but it takes a much longer time to be completely resorbed than the autogenous bone graft, and it showed statistical significant bone graft volume stability.