Guided Bone Regeneration (Osteopromotion)
In guided bone regeneration, a membrane (nonresorbable or resorbable) is used to cover an area where bone graft healing or bone regeneration is desired. The concept c’: guided regeneration, or osteo rornotion, is
based o , the ability to exclude undesirable cell types, such a’ epithelial cells or fibroblasts, from the area where bone healing is taking place. .
In 19H2, Nyman 19 described a technique to improve periodontal ligament regeneration using a membrane barrier to exclude undesirable cells from the area where periodontal ligament healing or regeneration was required. Dahlin er al20 showed that bone growth around implants couled be facilitated using a similar technique. By placing a membrane covering over a bone graft,” aster-growing fibroblasts and epithelial cells can be walled off, allowing bone to grow in a relatively protected environment.Many type~ 01 materials have been used as membrane coverings. Currently, expanded olytetrafluorocthylenc
(el’Fl’Lt membrane is the most popular.’ This membrane is not resorbable and must be removed after adequate bone .healing occurs. Resorbable membranes such as homologous grafts and genetically engineered materials such as collagen, eliminate the need for a second surgical procedure for removal. These materials and the concept of guided tissue regeneration arc discussed fully in chapter 14.