Bone Regeneration
aka GUIDED BONE REGENERATION
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Before Guided Tissue Regeneration
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After Guided Tissue Regeneration
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In the past teeth were often removed without placing bone graft into the site to preserve the shape of the jaw. Once the tooth is missing, the body no longer needs to maintain the width of the jaw which previously accommodated the tooth. Therefore the jaw bone shrinks in width and the gum tissue follows. This can lead to a deficient jaw bone which is too narrow or short to accommodate an implant.
Today it is possible to preserve the shape of the jawbone at the time of tooth removal and regenerate bone previously lost from prior extractions through Bone Regeneration.
Socket preservation is the procedure in which bone grafting is performed at tooth removal. This procedure can result in preservation and augmentation of the bone which surrounds the tooth. Tooth removal must be carried out conservatively to promote fast and pain free healing. This is best performed using the surgical microscope and microsurgical techniques. The tooth socket is then grafted with a combination of different bone graft materials , each with specific properties , to maximize the amount of bone regeneration. The bone graft is then covered with a type of collagen barrier to contain the graft and separate it from the gum tissue. The gum tissue is then conservatively advanced to reduce the exposure of the graft to the oral environment. Socket preservation usually takes about 1.5-2 hrs to complete. It is generally associated with little discomfort and no swelling. The greatest inconvenience after the procedure is the patient needs to chew softer foods on the opposite side of the mouth for 2-3 wks. Four months after the procedure the patient is ready for implant placement.
If the patient has already lost bone structure from previously removed teeth and requires regeneration prior to implants the procedure is very different. As an analogy, pretend the wood floor (bone) under a carpet (gum tissue) has a large hole. The carpet is now displaced into the wood floor. The furniture in the room (pressure from other forces; lips, cheeks, eating) also resides over the hole and places presssure in that spot. In order to restore the hole, the wood floor would need rigid struts to bridge the gap in the floor. A non rigid material would not be able to withstand the pressure from the carpet and furniture and would collapse. This is often the situation with bone regeneration for implants (guided bone regeneration- GBR).
When bone is lost after tooth removal, this is analogous to the hole in the wood floor. To regenerate the bone, materials are used to maintain the desired shape of the bone under the gums, and bone graft is placed within that shape. The shape can best be maintained using rigid materials/barriers (non resorbable) not resorbable. Non resorbable materials mean that they need to be removed at a secondary procedure. Resorbable materials are indicated when the amount of bone missing is minimal (a very small hole in the floor). Over time resorbable materials become compressed from the pressure of the gum tissue, lips, etc and the desired result is not obtained.
Most practitioners are not comfortable using rigid materials. This is a very technique sensitive procedure which requires much training, skill and time to perform without complications. Practioners are also concerned that using non-resorbable materials is a two step surgical visit and therefore more invasive for patients.
Dr. Kissel has a method to use these materials with little complications resulting in excellent bone regeneration. He also uses resorbable materials but only when they are indicated, rigid materials are often the best way to completely restore a bone deficiency.
