During a sinus lift, the sinus floor above the upper jaw bone is elevated, to make room for the implant.
The bone in the upper jaw often is very thin and in close proximity to the sinus. This can make it difficult to place implants. For this reason we do a sinus lift. There are 2 main methods, the open/external and the closed/internal sinus lift.
During the open/internal sinus lift, a small bony window is pushed into the sinus. The implant then is screwed into the space that is now available. The rest of the space then is filled with bone replacement material or autogenous bone (bone that is collected from elsewhere in the mouth or body). After the healing process is finished, the implant will completely be covered by bone.
In the closed/internal sinus lift, the membrane of the sinus floor is lifted via the drill hole for the implant. The bone augmentation material is pushed through this drill hole under the sinus membrane, that is raised like a balloon. As a last condensing measure the implant is screwed into place. This method is a lot less invasive, however, depending on the remaining bone high, the external method has to be used if not sufficient bone height is present.