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 making many patients unsuitable candidates for the placement of dental implants. But, today we have the ability to grow bone where needed, giving us the opportunity to place implants of proper length and width. It also gives us a chance to restore functionality and esthetic 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, your own bone can be taken from your jaw, hip or tibia. Sinus bone grafts are also performed to replace bone in the posterior upper jaw. In addition, special membranes may be dissolved under the gum to protect the bone graft and encourage bone regeneration. This is called guided bone regeneration or guided tissue regeneration.
Major bone grafts are typically performed to repair 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, hip, and lateral knee 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 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.
If enough bone between the upper jaw ridge and the bottom of the sinus is available to stabilize the implant well, 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
In severe cases, the ridge has been reabsorbed 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 literally expanded by mechanical means. Bone graft material can be placed and matured for a few months before placing the implant.
Nerve Repositioning
As stated earlier, there are several areas of the body that are suitable for attaining bone grafts. In the maxillofacial region, bone grafts can be taken from inside the mouth, in the area of the chin or third molar region or in the upper jaw behind the last tooth. In more extensive situations, a greater quantity can be attained from the hip or the outer aspect of the tibia at the knee. When we use the patient’s own bone for repairs, we generally get the best results.
In many cases, we can use allograft material to implement bone grafting for dental implants. This bone is prepared from cadavers and used to promote the patients own bone to grow into the repair site. It is quite effective and very safe. Synthetic materials can also be used to stimulate bone formation. We even use factors from your own blood to accelerate and promote bone formation in graft areas.
These out-patient surgeries are performed under IV sedation or general anesthesia. After discharge, bed rest is recommended for one day and limited physical activity for one week.