The maxillary sinuses are behind your cheeks and on top of the upper teeth. Sinuses are like empty rooms that have nothing at all 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 an egg shell thin wall of bone separating the maxillary sinus and the mouth. Dental implants need bone to hold them in place so when the sinus wall is very thin, it is impossible to place dental implants in this bone.
There is a solution called a sinus graft or sinus lift graft. The dental implant surgeon enters the sinus from the side above where the upper teeth used to be. The sinus membrane is then lifted upward and donor bone is inserted into the floor of the sinus. Remember, 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 when years ago there was no other option other than wearing loose dentures.
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