Surgical technique using a window into the lateral wall of the maxillary sinus to gain access to the maxillary sinus membrane. Following mobilization and elevation of the sinus membrane, bone augmentation materials (i.e., autografts, allografts, alloplasts, xenografts, or combination mixtures) are used to elevate the sinus floor and allow the placement of dental implants. If the original bone height permits sufficient primary implant stability, then a simultaneous procedure can be used. Otherwise, a staged approach is recommended. Compare: Osteotome technique.