Procedures
Bone Grafting
Major & Minor Bone Grafting
Over a period of time, the jawbone in the area where teeth are missing atrophies or shrinks away. This often leaves poor quality and quantity of bone that is unsuitable for placement of dental implants. In this situation, the patient is not a candidate for implants unless more bone can be grown.
Today, we have the ability to grow bone where needed. This not only gives us the opportunity to place implants of proper length and width, it also gives us a chance to restore functionality and appearance.
Major Bone Grafting
Bone grafting can repair implant sites with inadequate bone structure due to previous extractions, gum disease or injuries. The bone can be obtained from a tissue bank or from your own jaw, or hip. Sinus bone grafts can be performed to replace bone in the posterior upper jaw. A collagen membrane is used that dissolves under the gum and protects the bone graft while encouraging bone regeneration. This is called guided bone regeneration or guided tissue regeneration.
Major bone grafts are typically performed to repair large defects of the jaws. These defects may arise as a result of traumatic injuries, tumor surgery, or congenital defects. Large defects are repaired using the patient’s own bone. This bone is harvested from a number of different sites depending on the size of the defect. The skull (cranium), and hip (iliac crest) are common donor sites. These procedures are routinely performed in an operating room and require a hospital stay.
Sinus Lift Procedure
The maxillary sinuses are behind your cheeks and on top of the upper teeth. Sinuses are like empty chambers filled with air. 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. Because dental implants need bone to hold them in place, it is impossible to place dental implants in this bone that is so thin.
The solution to this problem is a sinus graft or sinus lift graft. Dr. Pennington 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. 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 when years ago there was no other 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 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.
Ridge Expansion
This is a technique to restore lost bone when the jaw ridge has shrunk and is too thin to place conventional implants. In this procedure, the bony ridge of the jaw is literally expanded by mechanical means. Bone graft material is then placed and allowed to mature for a few months before placing the implant.
Nerve Repositioning
The inferior alveolar nerve, is the nerve that provides sensation to the lower lip and chin. This nerve runs through the lower jawbone and may need to be moved in order to make room for placement of dental implants in the molar area of the jaw. This procedure commonly results in some numbness of the lower lip and chin area and is used when other procedures are not possible.
Typically, an outer section of the lower jawbone is removed in order to expose the nerve and blood vessel within the boney canal. The nerve and blood vessel are then pulled to the side and the implants are placed. The nerve is then replaced into the canal and the surgical access is replaced.
When bone grafting is necessary, it is preferable to use the patient’s own bone for the best results. If for some reason this is not practical, allograft bone can be used. This is bone taken from cadavers and used to promote regeneration of the patient’s own bone. It is quite effective and very safe. Synthetic materials can also be used to stimulate bone formation and growth factors from your own blood can be added to accelerate and promote bone formation in the graft areas.