The maxillary sinuses are behind your cheeks and on top of the upper teeth. Sinuses resemble rooms that have nothing in them. Some of the roots of the natural upper teeth extend up into the maxillary sinuses. When these upper teeth are removed, there is often just a thin wall of bone separating the maxillary sinus and the mouth. Dental implants need bone to hold them in place. When the sinus wall is very thin, it is impossible to place dental implants in this bone.
But we can solve this problem using a procedure known as a sinus graft, or sinus lift graft. The dental implant surgeon enters the sinus from where the upper teeth used to be. The sinus membrane is then lifted upward, and the donor bone is inserted into the floor of the sinus. Keep in mind that the floor of the sinus is the roof of the upper jaw. After several months of healing, the bone becomes part of the patient’s jaw and dental implants can be inserted and stabilized in this new sinus bone.
The sinus graft makes it possible for many patients to have dental implants, whereas years ago there was no option other than wearing loose dentures.
If enough bone between the upper jaw ridge and the bottom of the sinus is available to stabilize the implant, sinus augmentations and implant placement can sometimes be performed as a single procedure. If not enough bone is available, the sinus augmentation must be performed first. The graft will mature for several months, depending upon the type of graft material used. Once it has matured, the implants can be placed.