About Bone Grafting

What is Jaw Bone Grafting (ridge augmentation) and why did my doctor say I needed a graft before I can get an implant?

The alveolar ridge of the jaw is the bone that surrounds the roots of teeth. When a tooth is removed an empty socket is left in the alveolar ridge bone. Usually this empty socket will heal on its own, filling with bone and tissue. The previous height and width of the socket will continue to deteriorate. Over a period of time, the jawbone associated with missing teeth collapses 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.

A ridge augmentation is a common dental procedure often performed following a tooth extraction. This procedure helps recreate the natural contour of the gums and jaw that may have been lost due to bone loss from a tooth extraction, or for another reason.

Dental implants require bone to support their structure and a ridge augmentation can help rebuild this bone to accommodate the implant.

How is the procedure accomplished?

A ridge augmentation is accomplished by placing bone graft material in the tooth socket. It is often done immediately after the tooth is removed to avoid the need for a second procedure later. Next, the gum tissue is placed over the socket and secured with sutures. Dr. Armanious may choose to use a space-maintaining product over the top of the graft to facilitate new bone growth. Once the socket has healed, the alveolar ridge can be prepared for dental implant placement.

A ridge augmentation procedure is typically performed in Dr. Armanious’s office under local anesthesia. Some patients may also request sedative medication.

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 - 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 - 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.

What is L-PRF?

Leukocyte Platelet rich fibrin (L-PRF) is a by-product of blood that is rich in platelets. Until now, its use has been confined to the hospital setting. This was due mainly to the cost of separating the platelets from the blood and the large amount of blood needed to produce a suitable quantity of platelets. New technology permits doctors to harvest and produce a sufficient quantity of fibrin from the same amount of blood drawn from the patient while they are having routine bloodwork. 

Why All The Excitement About L-PRF?

L-PRF permits the body to take advantage of the normal healing pathways at a greatly accelerated rate. During the healing process, the body rushes many cells and cell-types to the wound in order to initiate the healing process. One of those cell types is fibrin. Fibrin performs many functions, including formation of a blood clot and release of growth factors (GF) into the wound. These growth factors; platelet derived growth factors (PDGF), transforming growth factor beta (TGF), and insulin-like growth factor (ILGF), function to assist the body in repairing itself by stimulating stem cells to regenerate new tissue. The more growth factors released and sequestered into the wound, the more cells are stimulated to produce new tissue. Thus, L-PRF permits the body to heal faster and more efficiently.

A subfamily of TGF, is bone morphogenic protein (BMP). BMP has been shown to induce the formation of new bone in research studies in both animals and humans. This is of great significance to the surgeon who places dental implants. By adding PRP, and BMP, to the implant site with bone substitute particles, the implant surgeon can now grow bone more predictably and faster than ever before.

L-PRF Has Many Clinical Applications

L-PRF can be used to aid Bone grafting for dental implants. This includes onlay and inlay grafts, sinus lift procedures, ridge augmentation procedures, closure of cleft and/or lip, and palate defects. It can also assist in repair of bone defects created by removal of teeth, or small cysts and repair of fistulas between the sinus cavity and mouth.

L-PRF Also Has Many Advantages

• Safety: L-PRF is a by-product of the patient’s own blood, therefore, disease transmission is not an issue.
• Convenience: L-PRF can be generated in the doctor’s office while the patient is undergoing an outpatient surgical procedure such as the placement of dental implants.
• Faster healing: The supersaturation of the wound with L-PRF, and thus growth factors, produces an increase of tissue synthesis and faster tissue regeneration.
• Cost effectiveness: Since L-PRF harvesting is done with only a small volume of blood (as little as two test tubes) in the doctor’s office, the patient need not incur the expense of the harvesting procedure in hospital or at a blood bank.
• Ease of use: L-PRF is easy to handle and actually improves the ease of application of bone substitute materials and bone grafting products by making them more gel-like. 

Frequently Asked Questions About L-PRF

• Is L-PRF safe? Yes. During the outpatient surgical procedure a small amount of your own blood is drawn out via the IV. This blood is then placed in the centrifuge machine and spun down. In less than 15 minutes, the L-PRF is formed and ready to use.
• Should L-PRF be used in all bone-grafting cases? Not always. In some cases, there is no need for L-PRF. However, in the majority of cases, application of L-PRF to the graft will increase the final amount of bone present, in addition to making the wound heal faster and more efficiently.
• Will my insurance cover the costs? Unfortunately not. The cost of the L-PRF application (approximately $300) is paid by the patient.
• Can L-PRF be used alone to stimulate bone formation? No. L-PRF must be mixed with either the patient’s own bone, a bone substitute material such as demineralized freeze-dried bone (cadaver bone), or a synthetic bone product, such as BIO-OSS.
• Are there any contraindications to L-PRF? Very few. Obviously, patients with bleeding disorders or hematologic diseases do not qualify for this in-office procedure. Check with your surgeon and/or primary care physician to determine if L-PRF is right for you.

Bone Graft Substitutes

As a substitute to using real bone many synthetic materials are available as safe and proven alternatives, 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 that can be injected through a syringe.

Graft Composites
Graft composites consist of other bone graft materials and growth factors to achieve the benefits of a variety of substances. Some combinations may include: collagen/ceramic composite, which closely resembles the composition of natural bone, DBM combined with bone marrow cells, which aid in the growth of new bone, or a collagen/ceramic/autograft composite.

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. Armanious will determine which type of bone graft material best suited to your particular needs.

Bone morphogenic protein is an isolated protein that induces specific cells in our body to form new cartilage and bone. During surgery, the BMP is soaked onto and binds with a collagen sponge. The sponge is then designed to resorb, or disappear, over time. As the sponge dissolves, the bone morphogenic protein stimulates the cells to produce new bone. The BMP also goes away once it has completed its task of jump starting the normal bone healing process.

Since there is no need to harvest bone from the patients’ hip for BMP, recipients were spared donor site pain. Complications from the graft harvest site are also eliminated with the use of bone morphogenic protein.