Over time, the jawbone near missing teeth atrophies or can be reabsorbed. This normally leaves a poor quantity and quality of bone, making it ill-suited for placement of dental implants. In situations like these, most patients are not candidates for placement of dental implants.
Today, however, we are able to grow bone when needed. This gives us the opportunity to place implants of proper length and width. It also provides an opportunity to restore functionality and aesthetic appearance. Bone grafting can repair implant sites with inadequate bone structure from previous extractions, gum disease, or injuries.
Oral Bone Grafting Procedures
An alveolar bone graft is used for patients who have inadequate bone width and/or height in the area the dental implant is to be placed. Dental implants require adequate bone height and width in order to be stable. If there is not enough bone, a graft is done utilizing a patient’s own bone or a graft material to build up the ridge. Special membranes may also be utilized that dissolve under the gum and protect the bone graft and encourage bone regeneration. This is referred to as “guided bone regeneration,” or “guided tissue regeneration.”
Also, bone grafting can be performed at the time of tooth extraction. Donor bone is often used at this time to build up the ridge. Bone grafts typically need three to six months to heal prior to placing implants. The specific bone graft that will be necessary for your case will be discussed in detail with you during your consultation. This will include the surgical procedure, your post-operative course, as well as subsequent necessary steps.
Sinus Lift Procedure
A sinus lift procedure is used for patients who need dental implants but have thin sinus floors. Dental implants need bone to be present to hold them in place. When the sinus floor is very thin, it is not possible to place dental implants. To correct this, the surgeon enters the sinus from where the upper teeth used to be. These sinus bone grafts are performed to replace bone in the posterior upper jaw.
The sinus membrane is lifted and donor bone is inserted into the floor of the sinus. After several months of healing, the bone becomes part of the patient’s jaw. After the jaw is healed, dental implants can be inserted and stabilized in the new sinus bone. The sinus graft makes it possible to have dental implants when before, the only option was to wear 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.
In a few severe cases, the ridge has been reabsorbed. In these situations, a bone graft is placed to increase ridge height and/or width. This technique is used to restore the lost bone dimension when the jaw ridge gets too thin to place conventional implants. During this procedure, the bony ridge of the jaw is literally expanded through mechanical means. Bone graft material can be placed and matured for a few months before placing the implant.