Bone Grafting for Implants
Do I Have Enough Bone?
After tooth extraction, if the walls of the socket are very thick, they will usually fill naturally with bone in two to three months. However, when the walls of your socket are very thin (such as in your upper and lower front teeth), this type of healing will not be as predictable. In these situations, a bone graft is often placed at the time of tooth extraction to help your body fill in the empty socket with bone. This step will maintain the width and volume of bone you will need for implant placement several months later.
1. Inadequate Bone
2. Graft Material Placed
3. Implants Placed
There may be inadequate bone for implant placement if your tooth was removed many years ago and your bony ridge is extremely thin. In this case, a bone graft can be placed next to the thin bone and allowed to heal for up to six months. After the graft has fused to your pre-existing bone, the ridge will be re-entered and the implant placed. Bone grafting is usually a relatively comfortable office procedure. Many different bone-grafting materials are available, including your own bone.
1. Inadequate Bone
2. Graft Material and Implant Placed
You may also need bone grafting if the sinus cavities in your upper jaw are very large, or very low, and extend into the tooth-bearing areas. This often occurs when teeth in the back of a person’s upper jaw have been removed many years before, and the amount of bone available for implant placement is limited. A “sinus grafting procedure” is then required. Most often, it is performed in the office with local anesthesia and perhaps sedation. During this procedure, the membrane that lines the sinus will be located and elevated. Bone will then be added to restore the bone height and ensure that dental implants of an adequate length can be placed. This procedure often can be performed at the time of implant placement.
WHAT IS BONE GRAFTING?
Over a period of time, the jaw bone associated with missing teeth atrophies and is reabsorbed. This often leaves a condition in which there is poor quality and quantity of bone suitable for the placement of dental implants. In these situations, most patients are not candidates for the placement of dental implants.
With bone grafting we now have the opportunity to not only replace bone where it is missing, but we also have the ability to promote new bone growth in that location. 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 aesthetic appearance.
TYPES OF BONE GRAFTS
Autogenous Bone Grafts
Autogenous bone grafts, also known as autografts, are made from your own bone, taken from somewhere else in the body. The bone is typically harvested from the chin, jaw, lower leg bone, hip, or the skull. Autogenous bone grafts are advantageous in that the graft material is your own live bone, meaning it contains living cellular elements that enhances bone growth, also eliminating the risk of your body rejecting the graft material since it comes from you.
However, one downside to the autograft is that it requires a second procedure to harvest bone from elsewhere in the body. Depending on your condition, a second procedure may not be recommended.
Allogenic bone, or allograft, is dead bone harvested from a cadaver, then processed using a freeze-dry method to extract the water via a vacuum. Unlike autogenous bone, allogenic bone cannot produce new bone on it’s own. Rather, it serves as a framework, or scaffold, over which bone from the surrounding bony walls can grow to fill the defect or void.
Xenogenic bone is derived from non-living bone of another species, usually a cow. The bone is processed at very high temperatures to avoid the potential for immune rejection and contamination. Like allogenic grafts, xenogenic grafts serve as a framework for bone from the surrounding area to grow and fill the void.
Both allogenic and xenogenic bone grafting have an advantage of not requiring a second procedure to harvest your own bone, as with autografts. However, because these options lack autograft’s bone-forming properties, bone regeneration may take longer than with autografts, and have a less predictable outcome.
Bone Morphogenetic Proteins
Bone morphogenetic proteins (BMPs) are proteins naturally produced in the body that promote and regulate bone formation and healing.
Synthetic materials also have the advantage of not requiring a second procedure to harvest bone, reducing risk and pain. Each bone grafting option has its own risks and benefits. Dr. Reemer will determine which type of bone graft material best suited to your particular needs.