Minor & Major Bone Grafting
Over a period of time, the jawbone associated with missing teeth atrophies or shrinks. This often leaves a condition in which there is inadequate amounts of bone for the placement of dental implants. Today, we have the ability to grow bone where needed. 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 when before, implants were not possible.
Minor Bone Grafting
Minor bone grafting may consist of using human banked bone and/or your own bone. Bone substitutes generally do not require an additional site to procure the bone, whereas your own bone is generally taken from your upper and/or lower jaw. The type of bone utilized depends on many factors including, how much bone is required, what area needs to be grafted, and the specific desires of the patient. Socket preservation may be completed after a tooth is removed, prior to placing an implant, to regenerate bone in preparation for placing a dental implant. In general the graft is allow to heal for 4 to 6 months.
Major Bone Grafting
When there are larger defects, more bone is required for reconstruction. These defects may arise as a result of traumatic injuries, tumor surgery, or congenital defects. Large defects are generally repaired using the patient’s own bone. This bone is harvested from a number of different sites depending on the size of the defect. The back part of the lower jaw (ramus), the chin (symphysis), hip (iliac crest), and lateral knee (tibia), are common donor sites. This latter two types of grafts are usually completed in a hospital operating room.
Sinus Lift Procedure
The maxillary sinuses are air spaces located behind your cheeks and above of the upper teeth. When the upper teeth are removed, over time, the bone shrinks, leaving only a thin wall of bone separating the maxillary sinus and the mouth. This can leave inadequate bone to place dental implants.
The solution to this is called a sinus graft. Through an opening in the mouth, the sinus membrane is lifted upward and a bone graft is inserted between the sinus membrane and the floor of the sinus. After 4-6 months of healing, the graft becomes part of the patient’s own jawbone and dental implants can be inserted and stabilized in this new bone.
If a minimum amount of sinus bone is required, sinus grafting and implant placement can sometimes be performed as a single procedure. This minimizes the number of surgeries and shortens the healing time before the implants are ready to restore.
Ramus Graft Procedure
Occasionally, the jawbone is too narrow to have implants placed. This can be treated by placing a block of bone, usually taken from the back part of the lower jaw, and placing it in the area of the narrow bone. After allowing 4-6 months for the bone graft to consolidate, the jawbone should be wide enough to place the dental implants. All incisions are made inside the mouth and, since the amount of bone taken is small compared to the size of the jaw, there are no long-term esthetic changes in your appearance and the procedure does not weaken the jaw.
In some cases, the ridge is too narrow for implants and can be expanded by mechanical means. With this technique, the jaw is widened by splitting the bone, and a bone substitute or bone morphogenetic protein is placed within the intervening space. After 4-6 months for healing, the bone is healed, and implants can be placed.
Bone Morphogenetic Protein
Bone morphogenetic proteins (BMPs) are a group of growth factors present in the body which are known for the ability to induce the formation of bone. In recent years BMP’s have been produced using recombinant DNA technology and have been used for a number of years in orthopedic spine surgery. When used in oral and maxillofacial surgery, BMP’s are used to assist in growing additional bone to enable the placement of dental implants. BMP’s in many cases eliminate the need to procure bone from other body sites such as the jaw and/or hip, and is used in a liquid form which is placed in a surgical type of sponge. The sponge is placed where bone is desired and the BMP induces and attracts osteocytes or the cells which can grow new bone. This can eliminate or significantly decrease the pain associated with the bone grafting procedure, improve the amount of bone grown, and significantly reduce the downtime and recovery period for the patient.
The preparation of your mouth before the placement of dentures is referred to as pre-prosthetic surgery. Some patients require minor oral surgical procedures before receiving a partial or complete denture in order to ensure the maximum level of comfort. A denture sits on the bone ridge, so it is very important that the supporting bone is of the proper shape and size, and that the gum is firm, smooth, and well contoured. If a tooth needs to be extracted, the underlying bone may be sharp and uneven and require smoothing.