So you are missing a tooth, several teeth, or perhaps even all your teeth. And you are looking into having dental implants as part of your permanent tooth replacement solution. From times that go back millennia (no exaggeration) the practice of dentistry has addressed the problem of missing teeth. The revolutionary field of implant dentistry today enables people to have their teeth replaced with more precision and predictability than ever before.
It is no longer sufficient to ask whether an implant can be placed where a natural tooth once resided, but also how long can the implant will last. And just as important, what will the tooth being supported by the implant look and feel like after one week, after one year, and after five years? The answer to these questions is paramount in the careful planning of dental implant treatment and can be summarized in four words:
Is There Enough Bone?
The functional and cosmetic success of a dental implant, both short term and long-term, is critically dependent upon the amount and quality of bone that will receive and support it. Because of this, bone grafting plays a crucial role in implant dentistry.
Is Bone Grafting For Dental Implants Always Necessary?
It all depends on whether there is sufficient bone to meet the specific structural, functional, and cosmetic demands placed upon the planned implant and subsequent tooth replacement. These variables are different from patient to patient, as is the amount and density (hardness) of bone. Therefore, it is essential that the quantity and quality of bone is measured for each and every implant patient prior to actual implant surgery.
How is bone evaluated before implant placement?
The most accurate way to evaluate and measure the amount of bone in a prospective implant site is to scan the area using cone beam computed tomography (also known as CBCT). CBCT is an x-ray imaging technique similar to a medical CT scan but utilizes a mere fraction of the radiation. The entire scan is accomplished in seconds and does not require confinement in an enclosed area, which is a concern to some.
A CBCT scan generates a 3-D image of bone and provides information such as bone height, width, density, shape, and the contour and health of the adjacent teeth. It also reveals the proximity of vital structures like nerves, blood vessels, and the maxillary sinus.
CBCT, along with other sophisticated implant software programs, allow the dentist to evaluate the surgical site and make an informed decision if bone grating for dental implants is necessary. It also allows for virtual placement of the planned implant to ensure that there is sufficient bone support once it is placed.
With such pre-surgical diagnostic information available, the need for bone grafting before or during implant placement can be determined. CBCT imaging has virtually become the standard of care in 21stcentury implant dentistry.
What is bone grafting for dental implants?
Simply stated, bone grafting is a surgical technique in which an area that is deficient in bone (the recipient site) is built-up in volume with donor bone (a graft) from another source. There are essentially four types of bone grafts: autografts, allografts, xenografts and synthetic. The donor bone can be from the same patient (generally obtained from a different or adjoining area of the mouth) and is called an autogenous bone graft.
More commonly, the bone graft is an allograft, which is human bone obtained from a licensed tissue bank, much the way blood donations come from blood banks. Allografts are meticulously processed by removing all organic matter (potential antigens) and then sterilized with gamma irradiation. There have been no reported cases of disease transmission from dental allografts.
Xenografts are bone grafts derived from animal sources, most typically bovine. And, some techniques of bone grafting for dental implants use non-organic sources such as calcium sulfate, which is similar to Plaster Of Paris.
While each type of bone grafting material has unique properties unto itself, its function as a scaffold and space holder allows for replacement by the patient’s own bone through a process called guided tissue regeneration.
Most bone grafting for dental implants happens in the dental office using local anesthetic and with a focus on absolute patient comfort.
When is bone grafting for dental implants performed?
Bone grafting for dental implants is typically performed months before implant insertion. When circumstances preclude implant placement at the time of tooth extraction (immediate implant placement), bone grafting is often necessary to preserve the existing bone around the extraction socket and to promote the formation of additional bone.
Immediate implant placement (performed at the same time as tooth extraction) requires grafting to ensure there is proper bone volume around the integrating implant fixture and to prevent the bone loss normally associated with extractions.
Sometimes the existing volume of bone is so severely compromised that implant placement would be virtually impossible were it not for even more sophisticated approaches to bone grafting. Such bone deficiencies may require advanced surgical techniques and a team approach involving dental and orthopedic surgeons working together in a hospital setting. These situations go beyond the scope of this article, but it should be reassuring to know such possibilities exist – if you suffer from extreme dental dysfunction.
What could happen if you don’t have the recommended bone grafting for dental implants?
An implant replaces the root of the tooth being replaced. A crown is placed on the implant and is the replacement tooth. Therefore, if the root is not secure, the tooth will be in jeopardy.
A simple analogy to consider. A crown is a house. The implant is its foundation and the bone is the ground upon which everything is built. There’s a huge 58-story condominium building in San Francisco called The Millennium Tower. It was recently discovered that the building is not only tilting, but it’s sinking as well. Why? It turns out that the foundation was sunk into mud, fill, and sand, instead of into bedrock. It turns out that terra firma is not so firm after all. Not a good choice for a skyscraper that size.
Although The Millennium Tower’s foundation is supported by steel, the material it was embedded into is so weak that the entire building is now in jeopardy. A dental implant is just like a building foundation. Although the implant is made from super-strong titanium, the long-term success of the restored tooth is not guaranteed if the quality and quantity of bone is deficient. This along with proper design and good clinical skills will ultimately the determine success of treatment.
Advances in surgical technique and biomaterials, including bone grafting for dental implants, has made proper implant site development possible. It is this proper site development that helps safeguard against a sinking (not Sinkin) Millennium Dental implant Tower.
Conclusion: People who seek dental implants just want their teeth back. Understanding that dental implants are the means, and not the end, to regaining a beautifully intact, aesthetically pleasing, fully functional and natural feeling dentition that will stand the test of time is of paramount importance for those seeking successful implant dentistry.
And bone grafting for dental implants makes it possible.
Familiarizing yourself with implant dentistry will help ensure that the care you receive is the care you desire. Link here to find out more about dental implants.