This article is a follow-up to a video from 2009 that I receive a lot of questions about. Block bone grafting for dental implants is still a very successful procedure…. But a lot has changed over the years!
(side note: Many people mistake the term “graft” with “graph.” The correct term is “graft”)
Basics on Block Grafting
I highly suggest you watch the video and read this post. You’ll gain excellent information from both to help you make an informed decision if this is something you’re considering.
A block bone graft is done when there is a large section of bone that is missing. That area of missing bone is usually the outer wall of bone that faces your cheek. A block bone graft is needed when there is no way to put particulate bone particles into a “hole” like an extraction socket. The block bone graft attaches by screws to your jaw kind of like an orthopedic surgeon who is fixing a broken leg with screws. The screws are only kept in during the 4-6 months that the bone is reconnecting to your own existing bone.
Where you get the bone from ? Using your own bone is the best. But for smaller grafts, human tissue allograft can be used.
Advantages of Human Donor Bone Blocks
Over the last 15 years doing block bone grafts for dental implants I have used a combination of human donor block bone graft (allograft) and block grafts from your own body (autograft). Using block bone graft from your own body requires that I have to cut a piece of bone from your chin under the roots of your lower front teeth) or from the area where your lower wisdom teeth are or used to be. Cutting this piece of bone has its own risk factors especially the risk of permanent or temporary numbness because the nerves are close to the area where the bone has to be taken from. Using bone from a tissue donor has an unlimited supply so we don’t have to worry about the bone taken from these areas as not being enough.
Block Graft From Me
What experienced dental implant surgeons around the world have agreed upon is that block bone grafts using your own bone tend to be “avascular.” This means that they do not have a good blood supply…unless they are THINNED with purposeful space underneath! Getting blood into the bone graft to bring it back to life is the key to success of a bone graft. Even though the bone is taken from your own body, sometimes that outer wall we call cortex is too hard and does not get good permeation of blood vessels called capillaries.
The addition of molecular enhancers and growth factors made from your own blood has also changed…. technology is evolving!! The use of L-PRF, PRP and PDGF made from your own blood tremendously helps a block bone graft. These are made from drawing a little bit of blood at the beginning of your IV sedation and concentrating your own natural growth factors from your own blood . The growth factors and even stem cell will be reimplanted into the bone graft area…. This is truly awesome.
Bone From Another Person is Dead
Accredited tissue banks have learned how to properly harvest this bone also. The type of bone I use has origin from the vertebrae (back bone) of another human being. Remember that this bone is 100% dead. Nothing is alive in it. It has undergone severe radiation treatment to kill everything. Your own body will make it alive again. Some small gaps around the bone graft may be filled in using cow bone which is also very safe and well documented over several decades now.
What hasn’t changed is the surgical ability to do this procedure and the ability for you to heal very well. This is definitely a procedure for a very advanced dental implant surgeon with a lot of experience. This would not be the type of bone graft for novice. You as the patient must also be healthy. Smoking , substantial alcohol use and diabetes would be significant risk factors and lowers the success of any dental bone graft and implant procedure.
The examples shown should help for you to understand why a block bone graft is done. On the first images you can see the bone in cross section taken from a 3-D scan. The bone is too narrow to accept the diameter of the virtual dental implant which is outlined over the bone. In order for dental implant to be successful there needs to be an abundance of bone especially on the outer wall of the implant for it to be stable long-term and last a long time. You can see on the images where the bone graft was completed and the screw is holding in the bone.
Block Bone Graft Procedure
The gum is lifted, your own bone is prepared in order to receive the cadaver bone and that block bone graft is then screwed to your existing bone. The bone graft is hydrated in your own natural growth factors before it is screwed to your bone. The gum is passively covered back over the top and the block bone graft is allowed to heal for 4-6 months prior to removing the screw that holds the bone graft and placing the dental implant. A special type of temporary must be used for this bone graft if it is for a front tooth.
You can see the massive addition of volume that was added. The 3-D scan that was taken after the bone graft shows that same outline implant now sitting in a proper amount of bone. This will make the dental implant procedure extremely successful from a biological standpoint and from a cosmetic standpoint. When all of the bone is present both vertically and horizontally, there will not be open black triangles between the teeth which can be unsightly especially if it is the upper front area. The teeth on either side must have very healthy bone levels for this to occur. You cannot do a bone graft next to unhealthy teeth.
Block bone grafting using human tissue allograft from a cadaver is no longer a last ditch effort. Of course there are so many different ways to rebuild bone from bone widening expansion, socket bone grafting, sinus lifting, nerve repositioning, guided bone regeneration with membranes
…. So there is no one solution for everyone. Your case must be studied carefully to determine what is going to be the safest procedure with the best outcome.
The block bone graft for dental implants is typically done in areas of the upper front and side teeth. All photos are surgeries performed by me.
Ramsey A. Amin, D.D.S.
Diplomate of the American Board of Oral Implantology /Implant Dentistry
Fellow-American Academy of Implant Dentistry