Overview of Bone Grafting

What is Bone Grafting?

Over time, a jawbone with missing teeth atrophies (shrinks) or is reabsorbed. This can result in inadequate bone suitable for placement of dental implants. Under these circumstances, patients are not good candidates for placement of dental implants.

By bone grafting, we can replace bone that is missing, and also promote new bone growth in that location. This allows us the opportunity to place dental implants of proper length and width to restore both function and aesthetic appearance.

Bone grafting can restore bone structure loss from previous extractions, gum disease, injuries and, in some cases, congenitally missing teeth. Donor bone may be obtained from a tissue bank. Alternatively, your own bone taken from the jaw, hip or tibia (below the knee) can be used. Sinus bone grafts are also performed to replace bone in the back part of the upper jaw.

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 may be repaired using the patient’s own bone. This bone is harvested from a number of sites depending on the size of the defect. The skull (cranium), hip (iliac crest), and lateral knee (tibia), are common donor sites.

Types of Bone Grafts

Autogenous Bone Grafts:

Autogenous bone grafts, also known as autografts, use 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 much of the graft material is live bone containing living cellular elements that enhance bone growth.

One downside to the autograft is that it requires a second procedure, done simultaneously, to obtain bone from elsewhere in the body. Depending on your condition, a second procedure may not be in your best interest.

Allogenic Bone:

Allogenic bone, or allograft, is bone harvested from a human 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 its own. Rather, it serves as a framework or scaffold which bone from the surrounding bony walls can grow into to fill the defect or void.

Xenogenic Bone:

Xenogenic bone is derived from non-living bone of another species, usually a cow (bovine bone). 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 into and fill the void.

Both allogenic and xenogenic bone grafting are advantageous in that they do not require a second surgical site, as with autografts. But, because these options lack autograft’s bone-forming properties, bone regeneration may take longer and is less predictable.

Bone Graft Substitutes

As a substitute to using real bone, several synthetic materials are available as safe and proven alternatives to autologous bone, including:

Demineralized Bone Matrix (DBM) /Demineralized Freeze-Dried Bone Allograft (DFDBA):

This product is processed allograft bone, containing collagen, proteins, and growth factors that are extracted from the allograft bone. It is available in the form of powder, putty, chips, or as a gel.

Bone Morphogenetic Proteins:

Bone morphogenetic proteins (BMPs) are proteins naturally produced in the body that promote and regulate bone formation and healing.

Synthetic materials 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. The doctors at Centrasota Oral & Maxillofacial Surgeons will determine with you which type of bone graft material is best for your particular situation.