Do You Need a Dental Bone Graft?
Dental Bone grafts are highly successful in extraction sites. We fill those sites with two types of materials consisting of specially treated donor and synthetic material that I have successfully been using for over the years.
When we fill the hole left behind by the extracted root, surrounding bone cells use the graft in the following ways:
- The bone cells themselves are stimulated to make new bone (osteoconduction).
- Within the graft there are materials used by the bone cells as a scaffolding (like rebar) to populate the entire site (osteoinduction).
- Additionally, there are other materials that are used as food (substrate).
After placement of bone graft we seal it with a membrane. This keeps the gum cells out of the socket and lets the bone cells thrive (guided tissue regeneration).
The bone grafting technique described above works best in an intact extraction site. Badly infected teeth that have been left too long often destroy one or more walls of the tooth socket severely compromising the outcome of the described grafting.
What if Your Dentist Recommends a Bone Graft Before Receiving an Implant?
Patients often tell me they were told by another dentist to have bone graft material placed on top of the remaining bone which the dentist deemed insufficient to place implants. In many cases we find that opinion not to be true for one of two reasons:
- You can't place graft materials on top of bone and expect it to grow in the manner we have described above. You must place it within bone, not on top
- Often times we find that no graft is necessary because there is sufficient bone to receive implants. This opportunity presents itself differently in the upper and lower jaws:
- Upper (maxilla) and lower jaw (mandible):
- Bone on bone not possible
- Carefully placed narrow implants can often be placed in areas where other dentists say implants are not possible. Sometimes implants are placed at angles that would seem difficult to restore. Because implants are internally threaded and can receive the screw that holds the subsequent dental device at virtually any angle, angulation of dental implants (not perpendicular to a horizontal plain) does not disqualify their placement. The implant doesn't care at what angle the fastening screw attaches the dental crown or appliance to it.
- Lower jaw only (mandible):
- Placement of bone in severely compromised (atrophic) mandibular lower jaw bone is verified by a CT scan in order to evaluate the position of the mandibular nerve. Concerns about injuring the nerve often times disqualifies a patient for implants in this area.
- Where the height of the bone (radiographically) seems insufficient to receive an implant we often place an implant in front of the nerve which is itself within the bone. A subsequent regular x-ray (two dimensional) will make it look like it's within the bone. A subsequent, CT scan (three dimensional), will show the harmless relationship between the implant and the nerve Sometimes we do this procedure with virtually no anesthetic. This is not painful because the bone itself has no nerve and the gum is anesthetized. This technique is not painful and keeps the option open for the patient to let me know if I'm getting to close to the nerve.
- Upper jaw only (maxilla):
- Sinus grafting (sinus elevation / sinus lift) is generally recommended where insufficient bone remains because surrounding bone has been lost or the sinus is enlarged due to extraction of teeth adjacent to it (pneumanization). We normally use a CT scan to evaluate the entire upper jaw with regard to determining if there's sufficient bone to place implants.