Is Bone Grafting Necessary?
With the tooth in place, the surrounding bone is stimulated with each bite. Extracting the tooth leaves a large area with no bone (extraction socket) and immediately begins the process of resorption. There is continued loss of bone. Bone loss continues with time. The rate of loss depends on various factors and is not the same in all individuals. Some people lose bone much faster than others. Eventually, the bone resorbs to a level where replacement of the missing teeth with dental implants is not possible.
Types of Bone Grafting
Guided Tissue/Bone Regeneration
If a tooth socket is not grafted at the time of extraction, significant atrophy or bone loss may occur. If you desire an implant but there is not enough bone to accommodate it, a guided bone regeneration may be advised. Bone is grafted to the deficient area and covered with a membrane. This membrane will protect the graft while it is healing. Often, biologic bone growth accelerators are used in conjunction to help stimulate the graft and speed up bone growth. This can be done using allograft material, or donor bone, so a second surgical site to harvest bone is not needed. This takes 3-4 months or more to heal before and implant can be placed.
A sinus lift is used in the upper back jaw when there is not enough vertical bone for an implant. The graft is placed below the sinus membrane, essentially giving the sinus a “lift”. This is a common procedure performed either before the implant is placed or at the time of placement.
A socket preservation graft will prevent resorption of bone after an extraction. It is designed to preserve the same vertical and horizontal dimension of bone as when the tooth was present. This is performed on the same day as extraction. After the tooth is removed, the fresh socket is filled with bone mineral that acts as a scaffold or “place holder”. Your own native bone will replace the grafted bone in a few months, leaving a ridge more suitable for an implant. This takes 2-3 months to heal before an implant can be placed.
Veneer grafts are used when large amounts of bone are needed to graft a deficient area. These are taken from the patient’s own bone. They are usually harvested from the chin or from the back of the jaw by the wisdom teeth. The veneer graft is secured to the graft site with two mini titanium screws. Allogeneic graft or biologic growth accelerators may be used as well. The screws are removed when the implant is placed. This takes 5-6 months to heal before an implant can be placed.
Types of Bone Graft Material
The patient’s own bone is used as a graft to augment the desired area. This bone is usually taken from jaw. It can be harvested from the chin, or from the area near the wisdom teeth. The advantage to autogenous bone is that it contains the patients own bone cells and proteins. It can provide a scaffold for new bone to grow as well as signal the body to grow bone on its own.
Allogeneic bone is human bone that is processed and sanitized for use in bone grafting. It is provided by a FDA approved bone bank. This bone works extremely well as a scaffold for your body to use to grow bone. Most of this will be resorbed and replaced by the body’s own native bone. The majority of bone grafts performed in the office use allogeneic bone.
Xenogeneic bone is from a non-human source. Typically either bovine or porcine bone are used. These have been processed and sanitized in an FDA approved process at a national bone bank. Xenogeneic bone is sometimes added to other types of grafting when either a large volume is necessary or a longer lasting scaffold is necessary.
Biologic Bone Growth Accelerators
BMP (Bone Morphogenic Protein)
BMP is the protein that signals your body to create bone. When concentrated, it can be used alone or in addition to any type of bone substitute to regrow bone in even the most severe cases of bone loss. BMP is used mostly in sinus lifts and alveolar cleft grafting, but can be used off label in the upper and lower jaws to regenerate bone predictably.
PRF (Platelet Rich Fibrin)
PRF is derived from the patient’s own blood and contains fibrin and stem cells that can be mixed with the bone graft or added on top of a bone graft. PRF increases the quantity of available growth factors to enhance the body’s regeneration of new bone. This procedure is easily performed in the office at the same surgical appointment.
Emdogain is a protein-based gel that is derived from the cells in developing teeth. It is designed to promote predictable regeneration of lost hard and soft tissues around teeth. Dr. Loveless has been using it off-label to predictably salvage implants that have mild to moderate bone loss. Implants that others may deem unsalvageable can often be successfully grafted and stabilized for continued use.