Bone Grafting

What is purpose of bone grafting?
What are the different types of bone grafting?
Extraction site grafting
Horizontal bone grafting
Onlay bone grafting
Vertical bone grafting
Sinus lift bone grafting
Distraction osteogenesisv
Where does bone grafting material come from?
How does bone grafting heal?
Is bone grafting safe?
How successful is bone grafting?
What are the possible complications?
What type of prosthesis can I wear during healing?
How long before I can have dental implants and teeth?
Who is the right dentist for bone grafting and dental implants?

What is purpose of bone grafting?
Patients with tooth and bone loss suffer greatly from both functional and cosmetic problems. Conventional tooth replacement options, such as bridges or dentures, are inadequate for chewing, talking, and certainly for an acceptable smile. Bone grafting replaces and augments missing bone and support teeth in a natural way. Grafting promotes long-term success of dental implants, cosmetic results, hygiene, and longevity of your teeth.

What are the different types of bone grafting?
There are several bone grafting types based on need and defect. Extraction site preservation grafting is done at time of extraction to preserve or augment existing bone. Onlay bone grafting is done to increase bone width. Sinus lift bone grafting is designed to increase height of bone in the back of upper jaw. Distraction osteogenesis, although not technically a grafting procedure, allows increase in height of bone.

Extraction site grafting
Procedures to regenerate missing bone can begin at the same time as tooth removal. Many times if an implant cannot be placed immediately at the time of surgical removal of the tooth, a graft using bone from another area of the mouth, or synthetic bone can be placed into the tooth socket.

This graft will help to facilitate healing, provide bone for secondary implant placement, and preserve a significant amount of the gum tissue that would normally shrink during healing if the socket were allowed to collapse.

Many times a collagen membrane is placed to protect this graft during healing. There membranes may dissolve on their own or they may be removed later during the healing process if they do not dissolve.

If small defects are found following surgical tooth removal in areas where implants are to be placed, a graft using real or synthetic bone material can be used to fill in the defect. Since gum tissue grows faster than bone and will in essence invade the bone graft, causing it to shrink, a thin collagen membrane is used to cover the graft to prevent the gum tissue from growing into the area.

The bone replacement can usually be accomplished at the same time as dental implant placement, so no additional surgeries are necessary. This type of bone graft takes the same time to heal as it takes for the bone to remodel around the implant after it has been placed.

If a non-dissolving membrane is used, it is removed when the implant has bonded to the jawbone and the healing cap is placed. Some of the newer materials dissolve during the healing process and do not need to be removed.

Horizontal bone grafting
This is performed when the bone is too thin to support dental implants. Bone grafting increases the width and allows proper positioning of the implants. Procedure involves either an onlay bone against the existing ridge or expansion to increase it width.

Onlay bone grafting
Onlay bone grafting is used for horizontal bone augmentation. An actual block of bone is obtained from the chin or from where wisdom teeth are and placed to the area in need. These grafts typically require four to six months to heal and form new bone identical to the shape of the transplanted block. Implants can then be placed securely in this bone. It will usually take another three to four months for the bone to remodel around the implants. Implants placed in these grafts generally have the same success rates as implants placed in non-grafted bone.

Vertical bone grafting
Vertical bone grafting is indicated when the bone is too short.  This may occur from gum disease, trauma, tooth loss, or due to close proximity of sinuses in back of the upper jaw.  Bone grafting increases the bone height to support implants with ideal length and in ideal position for long term success. There are various treatment options based on location, degree of bone loss, and amount of bone augmentation needed.

Sinus lift bone grafting
Sinus lift is used for vertical bone augmentation and indicated when the bone height is inadequate for implants in the back of the upper jaw. The back of the upper jaw has been a problem for dental implant placement for decades. All of the sinus cavities are located above the teeth and jawbone. They tend to enlarge after tooth loss or removal, leaving very little residual bone for implant placement and stability.

In the early 1990’s a technique was discovered that allows your surgical specialist to literally push up the floor of the sinus cavity and add sufficient bone for implant placement. This is accomplished without going into the sinus itself, or changing the way that it functions.

This procedure allows ideal implant placement with success rates equivalent to placement in non-grafted bone. Often, the graft can be done at the same time as implant placement. The implants are then restored (replacement teeth placed) in approximately six months. If very little bone is present to start, the graft will need to be done first, with the implants placed after the initial six months of healing. The implants would then need another six months to bond to the newly formed bone before replacement teeth can be placed.

Distraction osteogenesis
This technique may be indicated for severe loss of bone height. It regenerates bone using a gradual “stretching” technique using special micro distraction device placed on bone.

Where does bone grafting material come from?
Bone-graft material may be in form of calcified granules such as demineralized freeze dried human bone, bovine bone, or synthetic materials provided in single pre-packed bottles.

Bone may also be obtained directly from the patient. Known as autogenous bone, it is considered the gold standard for bone grafting. Depending on the amount of bone necessary for grafting, it may be harvested from three sources:

Ramus (lower wisdom teeth area): Ideal for augmenting partial areas of bone deficiency

Chin: May be used as a second source if more bone is needed

Hip:  Indicated for very large defects where significant amounts of bone are needed. This procedure is performed in hospital under general anesthesia and patients often go home the following day. It is a relatively conservative procedure and patients recover remarkably well and quickly.

How does bone grafting heal?
Any type of bone-graft heals in four to six months during which body’s bone producing cells gradually replace the grafted material and form actual bone. Implants placed in these grafts generally have the same success rates as implants placed in non-grafted bone.

Is bone grafting safe?
Bone-grafts such as freeze-dried bone, bovine bone, and other synthetic materials have long history of safety and do not carry risks of disease transmission. Any bone obtained from a patient for their own surgery is also very safe and offers best type of bone for implant placement.

How successful is bone grafting?
Bone grafting is safe and predictable, and complications can be avoided when performed by a trained, skillful, and experienced oral surgeon using specialized instruments and techniques, proper tissue handling, recipient site preparation, and patients that adhere to important post operative instructions. Dr. Kazemi specializes in bone grafting and tissue regeneration procedures and has performed it successfully on thousands of patients. The office is designed and equipped for bone grafting and dental implant procedures, and the team assisting Dr. Kazemi is specially trained.  Methodical, exacting, and detailed protocols are followed strictly to make sure every patient is safe and having a pleasant experience. The fact is, regenerating lost bone is highly achievable with extensive clinical and scientific experiences to support it.

What are the possible complications?
Complications are relatively rare, but may include infection or opening of the overlying gum tissue and subsequent bone exposure (known as dehiscence). Exposure of bone during healing can lead to partial or complete loss of grafted bone. Nerve disturbances are remotely possible if surgery site is in close proximity, but it often resolves in a few weeks. Smoking, chewing hard food following surgery, and inadequate oral rinses can lead to inflammation, infection, or opening of gum tissue. and compromise healing. Therefore patient compliance during the recovery period is very important to success. Proper diagnosis along with meticulous surgical techniques minimizes risks and complications.

What type of prosthesis can I wear during healing?
A transitional prosthesis replacing the missing teeth may have been prepared by your dentist. Following bone grafting procedure, the prosthesis may be placed with minor modifications to avoid pressure on the graft. As it heals, the prosthesis may be further adjusted to improve its fit and stability until your permanent teeth are placed.

How long before I can have dental implants and teeth?
Dental implants may be placed four to six months following grafting procedure. Depending on implant location and type of grafting, temporary teeth may be placed at time of implant placement, several weeks later, or two to four months of healing.

Who is the right dentist for bone grafting and dental implants?
Bone grafting and teeth replacement with dental implants require collaborative efforts of a surgeon and a restorative dentist and dental laboratory. Bone grafting and implant placement are highly skilled disciplines, best performed by oral surgeons who are well trained and perform this procedure daily. Dr. Kazemi specializes in bone grafting and has performed it successfully on thousands of patients. The prosthetic aspect (crown, bridge, etc) is performed by your restorative dentist who may be a general dentist or a prosthodontist, a specialist trained in more complex aesthetic and reconstructive restorative dentistry.