Abstract
INTRODUCTION: Maxillary sinus septas are barriers of cortical bone that arise from the floor or from the walls of sinus and may even divide the sinus into two or more cavities. Morphologically maxillary sinus septa are generally oriented in buccopalatinal orientation horizontal or sagittal orientation of the sinus septa is a rare condition. PRESENTATION OF CASE: This report presents two sinus lift case, in which observed septa in a horizontal orientation was presented. Both cases were fixed by an implant supported prosthethic restoration. DISCUSSION: Surgeons must know detailed knowledge about maxillary sinus anatomy for successful sinus augmentation. Computed tomography (CT) is useful for examining the maxillary sinus. CONCLUSION: Horizontal-type sinus septa are rarely seen. Surgeons must be aware of septa types and orientations.