Bone Grafting

Bone grafting is a procedure which involves the replacement of missing bone with bone from another part of the patient’s body, bone from a donor or a substitute material. This surgical procedure is often necessary for patients undergoing dental restorations such as bridge work and dental implants. When a patient’s jawbone has either receded or become damaged, it will not provide sufficient support for implants. It is in such cases that bone grafting is necessary in order to provide a stable foundation for restorative work.

Reasons for Bone Loss

The stability and volume of the patient’s jawbone can be affected by a number of factors. The most common of such factors include:

Periodontal disease – Periodontal disease is the leading cause of bone loss in the oral cavity causing permanent damage to tissue and bone. When this disease affects the jawbone, it can ultimately lead to the loosening and loss of teeth as the support structures become progressively less stable. Dental injuries and infections — Trauma to the jawbone caused by physical injuries or oral infections can cause the jawbone to deteriorate and recede.

Tooth extractions — Tooth extractions typically lead to the loss of 40 to 60 percent of the surrounding bone over the three years following the extraction procedure.

Reasons for Bone Grafting

• Dental implants – Implants are the preferred replacement method for missing teeth because they restore full functionality to the mouth; however, implants need to be firmly anchored to the jawbone to be effective. If the jawbone lacks the necessary quality or quantity of bone, bone grafting can strengthen and thicken the implant site.
• Sinus lift – A sinus lift entails elevating the sinus membrane and grafting bone onto the sinus floor so that implants can be securely placed.
• Ridge augmentation – Ridges in the bone can occur due to trauma, injury, birth defects, or severe periodontal disease. The bone graft is used to fill in the ridge and make the jawbone a uniform shape.
• Nerve repositioning – If the inferior alveolar nerve requires movement to allow for the placement of implants, a bone grafting procedure may be required. The inferior alveolar nerve allows feeling and sensation in the lower chin and lip.

Types of Bone Grafts

There are several types of dental bone grafts. The following are the most common:

• Autogenous – This type of bone graft uses bone from the patient’s own body (often from another part of the jaw) to repair the damaged or deteriorated areas of the jawbone. Since the harvested bone comes from the patient’s own body, this method provides the most predictable and successful results and is therefore generally the preferred method.
• Allograft – Synthetic bone (manmade) can be created in the laboratory and used in the bone grafting procedure. Bone can also be obtained from a bone bank (cadaver bone).
• Xenograft – These grafts use cow bone which has been processed and sterilized to ensure that it is biocompatible.

When the human, cow or synthetic bone is added to the affected area it will fuse with the existing bone. While the entire process can take several months, bone grafting provides greater bone mass and therefore greater support for dental implants.