Dental Bone Grafting
What is Bone Grafting?
Bone grafting is where bone is built up or added to your jawbone when you don’t have enough to support the procedure you are looking to have performed. Bone grafting for dental work is often used for dental implants. In order for dental implants to be successful, the patient must have enough bone in their jawbone to support the implants. Winchester Oral Surgeons Dr. Coviello & Dr. Starley, will evaluate your jawbone and let you know if a bone graft is necessary prior to your dental work.
Common Causes for Jawbone Bone Loss:
Tooth loss & missing teeth – When a patient is missing one or more teeth, they generally start to experience gum recession and bone deterioration over time. When there are no teeth there to support and stimulate the jaw bone, it begins to break down over time. The body ‘no longer needs’ the jawbone in these instances. The rates at which the bone deteriorates can vary from patient to patient but generally starts within the first 18 months of tooth loss. This makes procedures such as dental implants vital to securing bone density.
Periodontal disease – Periodontal (gum) disease can also be a major contributor to bone deterioration. This disease can also coincide with tooth loss, as the bone starts to lose density.
Wearing removable dentures long term – Traditional long-term dentures can also lead to bone density loss, as the body loses the “need” for the jawbone without tooth support. The jaw becomes less stimulated and can start to break down over time.
Injury/face trauma – Common sources of trauma to the jaw that can lead to bone loss are: knocked out teeth, auto injury accidents, broken jaw/fractures and a history of trauma that leads to tooth loss.
Types of Bone Grafting
The maxillary sinuses are behind your cheeks and on top of the upper teeth. Sinuses are like empty rooms that have nothing in them. Some of the roots of the natural upper teeth extend up into the maxillary sinuses. When these upper teeth are removed, there is often just a thin wall of bone separating the maxillary sinus and the mouth. Dental implants need bone to hold them in place. When the sinus wall is very thin, it is impossible to place dental implants in this bone.
There is a solution and it is referred to as a sinus graft or sinus lift. The dental implant surgeon enters the sinus from where the upper teeth used to be. The sinus membrane is then lifted upward and donor bone is inserted into the floor of the sinus. Keep in mind that the floor of the sinus is the roof of the upper jaw. After several months of healing, the bone becomes part of the patients jaw and dental implants can be inserted and stabilized in this new sinus bone.
The sinus graft makes it possible for many patients to have dental implants when years ago there was no other option other than wearing loose dentures.
If enough bone between the upper jaw ridge and the bottom of the sinus is available to stabilize the implant well, sinus augmentations and implant placement can sometimes be performed as a single procedure. If not enough bone is available, the Sinus Augmentation will have to be performed first, then the graft will have to mature for several months, depending upon the type of graft material used. Once the graft has matured, the implants can be placed.
For sinus lift after surgery instructions please click this link!
When a tooth is extracted, it leaves behind an empty socket. Because there is no tooth to stimulate the jawbone, the socket may expand as the jawbone resorbs due to lack of use. Socket preservation is a preventative measure that is performed by implanting bone grafting material at the same time as extraction to preserve the jawbone for future tooth replacement.
Ridge expansion or augmentation is similar to socket preservation in that it involves the repair of the bone underneath an empty tooth socket. However, instead of being done at the same time as extraction (as with socket preservation), it is performed after bone resorption has already occurred. The treatment involves the implanting of bone grafting material in the site to act as scaffolding for new bone growth. In severe cases, the ridge has been reabsorbed and a bone graft is placed to increase ridge height and/or width. This is a technique used to restore the lost bone dimension when the jaw ridge gets too thin to place conventional implants. In this procedure, the bony ridge of the jaw is literally expanded by mechanical means. Bone graft material can be placed and will mature for several months prior to placing the dental implant.
The inferior alveolar nerve, which gives feeling to the lower lip and chin, may need to be moved in order to make room for placement of dental implants to the lower jaw. This procedure is limited to the lower jaw and indicated when teeth are missing in the area of the two back molars and/or 2nd premolar, with the above-mentioned secondary condition. Since this procedure is considered a very aggressive approach (there is almost always some postoperative numbness of the lower lip and jaw area, which dissipates only very slowly, if ever), usually other, less aggressive options are considered first.
Typically, we remove an outer section of the cheek side of the lower jawbone in order to expose the nerve and vessel canal. Then we isolate the nerve and vessel bundle in that area, and slightly pull it out to the side. At the same time, we will place the implants. Then the bundle is released and placed back over the implants. The surgical access is refilled with bone graft material of the surgeons choice and the area is closed.
Major Bone Grafting
Major bone grafts are typically performed to repair defects of the jaws. These defects may arise as a result of traumatic injuries, tumor surgery, or congenital defects. Large defects are repaired using the patients own bone. This bone is harvested from a number of different sites depending on the size of the defect. The skull (cranium), hip (iliac crest), and lateral knee (tibia), are common donor sites. These procedures are routinely performed in an operating room and require a hospital stay.
These procedures may be performed separately or together, depending upon the individual’s condition. As stated earlier, there are several areas of the body that are suitable for attaining bone grafts. In the maxillofacial region, bone grafts can be taken from inside the mouth, in the area of the chin or third molar region or in the upper jaw behind the last tooth. In more extensive situations, a greater quantity of bone can be attained from the hip or the outer aspect of the tibia at the knee. When we use the patients own bone for repairs, we generally get the best results.
In many cases, we can use allograft material to implement bone grafting for dental implants. This bone is prepared from cadavers and used to promote the patients own bone to grow into the repair site. It is quite effective and very safe. Synthetic materials can also be used to stimulate bone formation. We even use factors from your own blood to accelerate and promote bone formation in graft areas.
There are three types of bone graft procedures: autogenous, allograft, and xenograft.
Autogenous grafts take bone from one area of the patient’s body and transplant it to the location in the mouth being restored. The bone is usually taken from nonessential bones such as the chin area. The benefit of an autogenous bone graft is that the bone used comes solely from the patient, thus reducing the likelihood of rejection and infection. The bone is also still “live”, meaning it still has active cellular material.
Allografts also use human bone transplanted to the area in the mouth being restored. However, allografts do not use the patient’s own bone. Instead, the bone usually comes from cadaver bone donated to bone banks. All allograft bone material is carefully screened and is considered very safe. Xenografts also replace bone in the area requiring treatment, however the bone comes from a non-human source. Usually the non-human source is bovine, or cow.
Allografts and Xenografts are used because they do not require a second surgical site to harvest bone and ample amounts of bone can be easily attained. Xenografts are often preferred when extra bone is needed to proceed with a dental implant procedure.
These surgeries are performed in the in-office surgical suite under IV sedation or general anesthesia. After discharge, bed rest is recommended for one day and limited physical activity for one week.
For Post-Op instructions follow this link!