Bone Grafting for Implant Placement
Not all jawbones are ideal for implant placement. For example, a bone grafting procedure may be required either at the time of implant placement or as a separate procedure prior to implant placement.
Socket Bone Grafting
At the time of extraction, periodontist will determine whether or not the extraction site is a good candidate for immediate implant placement. If not, patient will receive a socket bone grafting where bone materials are placed into the extraction socket. Depending on the situation, a barrier membrane may be placed over the grafting materials. A period of usually 3 months is allowed for the bone to mature to then receive the dental implant screw.
It is well known that following extraction, jawbone will reshape itself at the extraction site by losing some bone. Some individuals will lose more bone than others. Socket bone grafting is therefore important because it will reduce the chance of patients losing too much jawbone after extraction. Not only does socket bone grafting help patients to maintain as much as possible the volume of the jawbone at the extraction site, it also helps to build the gums around extraction site because the contour of the gums is determined by the contour of the jawbone. Therefore, from both functional and esthetic standpoint, it is critical that a socket bone grafting is done at the time of extraction. Even if the patient is not planning to have dental implant therapy to replace the missing tooth after extraction in the near future, a socket bone grafting is still recommended because
- it can build the bone and gum volume needed to help the dentist to make a nice-looking dental bridge over the extraction site,
- it can help to maximize the volume of jawbone, providing stronger support for the denture,
- it can slow down the progression of maxillary sinus pneumatization (upper back teeth),
- it may reduce the risk of dry socket following extraction,
- it is relatively simple to perform surgically,
- its post-operative healing experienced by the patient is similar to if no socket bone grafting is done,
- in case the patient changes his/her mind years later and wants to have a dental implant, the patient will more likely to still have enough bone to have implant screw placed without additional bone grafting procedures.
It is well known that after tooth removal the jawbone will remodel and become atrophic in volume over time. As such, many individuals who have lost their teeth for many years have inadequate amount of bone for dental implant placement.
Ridge augmentation is an advanced bone grafting procedure that helps to build new bone over the atrophic jawbone in preparation for implant therapy. If the atrophy of jawbone is not so severe, ridge augmentation can be done at the same time with implant placement. If jawbone has lost its volume extensively, a separate ridge augmentation procedure will be performed. Ridge augmentation procedure involves the use of bone grafting materials, barrier membranes, possibly some tenting/fixation screws, and growth factor(s). If a separate ridge augmentation procedure is done, the patient will need to wait for a period of at least 6 months before undergoing dental implant placement.
Maxillary Sinus & Nasal Bone Grafting
Situated on top of the upper back teeth are the maxillary sinuses. Following extraction of upper back teeth, the maxillary sinus will usually expand in a process known as maxillary sinus pneumatization. This pneumatization will lead to loss of jawbone height. If the loss is extensive, a maxillary sinus bone grafting procedure will need to be done either prior to or at the same time of dental implant placement.
There are essentially two types of surgical techniques utilized in maxillary sinus bone grafting. One procedure involves opening a window on the lateral side of the maxillary sinus to facilitate the placement of bone grafting materials inside the sinus. The other procedure involves gaining access from the base of the sinus to place bone grafting materials. In both situations, the Schneiderian membrane (the lining of the maxillary sinus cavity) will be lifted so in reality the bone grafting materials are not placed inside the maxillary sinus but below the sinus where it is needed for implant placement. Immediately following the procedures, it is not uncommon for patients to experience some minor nose bleeding and sinus congestion.
In nasal bone grafting, the base of the nose is lifted up and the bone grafting materials are placed right under the nose. Nasal bone grafting is indicated for the placement of dental implants at the front area of the upper jawbone where there is inadequate jawbone height.