Over a period of time, the jawbone associated with missing teeth atrophies or is reabsorbed. This often leaves a condition in which there is poor quality and quantity of bone suitable for placement of dental implants. In these situations, you may need bone grafting for placement of dental implants.
Today, we have the ability to grow bone where needed. This gives us the opportunity to place implants of proper length and width, in patients who have diminished bone due to tooth loss.
Major Bone Grafting
Bone grafting can repair implant sites with inadequate bone structure due to previous extractions, gum disease or injuries. The bone is either obtained from a tissue bank or your own bone is taken from the jaw. Sinus bone grafts are also performed to replace bone in the posterior upper jaw. In addition, special membranes may be utilized that dissolve under the gum and protect the bone graft and encourage bone regeneration. This is called guided bone regeneration or guided tissue regeneration.
Sinus Lift Procedure
The maxillary sinuses are beneath your cheeks and on top of the upper teeth. Sinuses are holes in our skull that usually 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.
There is a solution and its called 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 donor bone is inserted into the floor of the sinus. After several months of healing, the bone becomes part of the patients jaw and dental implants can be inserted and stabilized in this new bone.
This sinus graft makes it possible for many patients to have dental implants when years ago there was no other option other than a removable denture.
If enough bone between the upper jaw ridge and the bottom of the sinus is available to stabilize the implant, sinus bone grafting and implant placement can sometimes be performed as a single procedure. If not enough bone is available, the sinus graft will have to be performed first, then the graft will have to mature for several months, depending upon the type of graft material used. Once the graft has matured, the implants can be placed.
In severe cases, the ridge that used to hold teeth reabsorbs and a bone graft is placed to increase ridge height and/or width. This is a technique used to restore the lost bone dimension when the jaw ridge gets too thin to place conventional implants. In this procedure, the bony ridge of the jaw is augmented with a bone graft or expanded by mechanical means. The bone graft material needs to mature for a few months prior to placing the implant.