Why Bone Grafts May Be Needed For Dental Implants
Dental implants have become highly utilized in dentistry. Oftentimes, another procedure called a bone graft, is required to aide in the stabilization of dental implants. The success of dental implants depends on the quality and quantity of bone present. If the bone is of poor quality or low quantity the dental implants have a much lower chance of success. Adequate bone structure is required for a dental implant to integrate (become one with the surrounding bone), and be strong enough to chew on. Bone grafting is a surgical procedure that can increase the quality and/or quality of the bone to then directly effect the chance of dental implants success. Not all dental implants require bone grafts, so when do you need them?
When Are Dental Bone Grafts Needed For Dental Implants?
-The existing bone has insufficient width. This could be a genetic factor where the bone width is lacking naturally or it could be from damage over time from periodontal disease.
-The existing bone has insufficient height. The height of the bone is just as critical as the width as it ensures the dental implant is properly anchored to support the stress of function (biting and chewing food).
-The maxillary sinus is too close to area of placement. This usually means that there is not enough bone between the tooth area and the sinus. Generally this can be fixed by lifting the sinus membrane (Sinus Lift) and placing bone graft material.
-Inadequate bone as a result of previous tooth or teeth removal. Sometimes when teeth are removed or fall out, bone can be removed as well. The bone will also decrease and remodel once the tooth is removed as it no longer is needed to hold a tooth in place.
-Not enough bone due to periodontal disease or trauma. Periodontal disease and trauma can lead to there not being enough bone for a successful dental implant.
-Inadequate bone due to defect in development that affects growth of bone in the jaw.
-Insufficient bone caused by the removal of cysts or tumors in the mouth. If the removal of a cyst or tumor is required there will also be removal of some of the bone, there may not be enough left for the dental implant to be successful. After removal of oral pathology, healing time is required so that bone quality and quantity can be reevaluated.
Bone Grafting Procedure
Where Does the Bone Come From?
Bone grafting procedures involve the use of your bone, cadaver bone, cow bone, and synthetic bone. Your own bone will most likely come from your chin or ramus (the back part of your lower jaw). If your dentist is unable to get enough bone from either of these areas, they may need to get bone from your hip or shin bone (tibia) instead. The hip is considered to be a better source because the hip bone can provide a large amount of bone. The marrow from either the hip or shin (tibia) contains bone-forming cells. However bone taken from your hip requires a visit to the hospital along with general anesthesia. Cadaver bone and cow bone is sterilized and broken down into small chips for easy placement. Man made synthetic materials are also widely used for bone grafting. The synthetic bone acts as a scaffold for new bone to build on.
Newer products containing growth factors have also been developed. Some are used to enhance bone graft materials and others are used in place of bone grafting. One of these products, BMP-2 stimulates certain body cells to turn into bone. The BMP-2 protein occurs naturally in the body.
What Happens During Bone Grafting?
A good example is a patient that needs to have a single tooth extracted and wants to have it replaced with a dental implant and dental crown. There may be a bone defect in the area or the tooth is large and needs to have some bone placed to fill in the expansive space. In this case, a dental bone graft is ideal and necessary to support the future dental implant.
Before the procedure, you will need to have either a CT scan or a cone-beam computed tomography (CBCT) scan. The images of a CT or CBCT provide valuable information about bone quantity and show where important nerves and sinuses are located which need to be avoided. A CBCT actually provides a 3-D image of your bone and any defects present. Local anesthesia will be used to numb the area where the bone augmentation is needed (called the recipient site) as well as the area from where bone will be removed (donor site) if using your own bone. An incision in the gum tissue where the implant will be placed is made to determine how much and what type of bone is needed.
The most common type of graft is called a socket graft. This is used to fill the space left behind by the lost tooth. The material used most often in a socket graft is often comprised of cow bone. This bone is harvested from known healthy cows and is processed through a freeze drying procedure that renders a sterile end product containing only the mineral content of natural bone. The graft is applied to the empty hole immediately after a tooth extraction and is secured using sutures (stitches).
Following the bone grafting procedure the patient will be given antibiotics, pain medicine, and an antibacterial mouthwash. You will need to avoid certain foods. You also will be told how to avoid putting pressure on the area or damaging it while it heals. If you wear a denture, you may not be able to wear it for a month or longer while the area heals. If you have natural teeth around the bone graft, your dentist may make a temporary removable bridge or denture to help protect the area.
Success of Bone Grafting
The success rate for bone grafts in the jaws for the purpose of placing dental implants is very high. However, there is a small chance that the bone graft will fail, even if your own bone was used. Bone grafts are not rejected like organ transplants. It is not exactly known why some dental grafts fail. There is a higher risk of failure in patients with diabetes, who smoke, or have periodontal disease. A failed graft can be removed. Once the area has healed, your dentist may choose to place a second bone graft.
Dental Bone Grafts Conclusion
Without dental bone grafts many would be unable to restore their smiles with dental implants. Just like dental implants, dental bone grafts are highly successful procedures to restore a smile to its natural state. Every case is different and the need for bone grafting varies from person to person and tooth to tooth. You can discuss the need for possible bone grafting with your dentist to see if it would benefit your procedure.