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, most patients are not candidates for placement of dental implants.
Today, we have the ability to grow bone where needed. This not only gives us the opportunity to place implant of proper length and width, it also gives us a chance to restore functionality and esthetic appearance.
Major Bone GraftingBone 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, hip, or tibia (below the knee.) 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.
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 (cranium), hip (iliac crest), and lateral knee (tibia) are common donor sites. These procedures are routinely performed in an operating room and require a hospital stay.
What is a sinus lift?
The maxillary sinuses are behind your cheeks and on top of the upper teeth. These sinuses are empty, air-filled spaces. 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.
The key to a successful and long-lasting dental implant is the quality and quantity of jaw bone to which the implant will be attached. If bone loss has occurred due to injury or periodontal disease, a sinus augmentation can raise the sinus floor and allow for new bone formation. A sinus lift is one of the most common bone grafting procedures for patients with bone loss in the upper jaw. The procedure seeks to grow bone in the floor of the maxillary sinus above the bony ridge of the gum line that anchors the teeth in the upper jaw. This enables dental implants to be placed and secured in the new bone growth.
Am I a candidate for a sinus lift procedure?
A sinus lift may be necessary if you:
- are missing more than one tooth in the back of your jaw
- are missing a significant amount of bone in the back of your jaw
- are missing teeth due to a birth defect or condition
- are missing most of the maxillary teeth and require support for dental implants
How is a sinus lift accomplished?
Most commonly, a small incision is made on the premolar or molar region to expose the jaw bone. A small opening is cut into the bone, and the membrane lining the sinus is pushed upward. The underlying space is filled with bone grafting material, either from your own body or from a other sources. Sometimes, synthetic materials that imitate bone formation are used. After the bone is implanted, the incision is sutured and the healing process begins. After several months of healing, the bone becomes part of the patient’s jaw and dental implants can be inserted and stabilized in the newly formed sinus bone.
If enough bone between the upper jaw ridge and the bottom of the sinus is available to sufficiently 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 up to several months, depending upon the type of graft material used. Once the graft has matured, the implants can be placed.
The sinus graft makes it possible for many patients to have dental implants that previously had no other option besides wearing loose dentures.