Unfortunately, when teeth are pulled, the remaining jawbone begins to change, with the bony ridge losing height and width over time. Studies have shown that the most rapid and extensive changes occur in the first six months after tooth extraction. If these changes are not taken into consideration, the implant may end up in the wrong position, relative to the opposing teeth. If this happens, the resulting restoration may become compromised. The restoration may require contours that are difficult to keep plaque-free and healthy. Normal chewing forces may result in abnormal forces being applied to the implant, which can lead to mechanical failures such screw loosening, screw breakage, bone loss around the implant and even implant fractures.
In order to prevent these types of problems from happening, implants must be placed in the correct positions. If the bone is deficient in these positions, various bone grafting/regeneration techniques are employed to regenerate what is needed.
Bone grafting is commonly done in implant dentistry. Typically, the implant is placed using a positioning guide, and a portion of the implant has deficient bone height or thickness around it. Bone particles are placed into the deficient areas and covered with a dissolving or non-dissolving barrier membrane. This separates the graft from the overlying gum tissues, allowing the graft to integrate with your bone, while at the same time, the implant is attaching to your jawbone.
Occasionally, the amount of jawbone present is insufficient to place an implant. In these cases, bone grafting is done ahead of time and several months later, the implants are placed into the grafted bone. This type of grafting can get quite complex, time consuming and expensive. This is why we recommend placing implants as soon as possible after a tooth is lost.
As we get older, our sinuses tend to expand and grow larger at the expense of our upper jawbone. This is of little consequence...until back teeth are lost. When upper back teeth are lost, and implants are desired, there often is too little jawbone ridge height remaining below the sinus floor to hold an implant. Fortunately, we can overcome this through a procedure called a sinus lift.
The sinus is basically an air cavity that is lined by a membrane that fortunately, can be carefully lifted from the bone and bone graft material can be placed into the created space. The graft is eventually replaced by the patient's bone and is suitable for attaching to and holding a dental implant. Amazingly, with careful technique and proper care after the procedure, recovery is usually comfortable and uneventful. Sinus lifts are a common procedure in implant dentistry today and research shows that implants placed into the grafted bone have very high success rates.