Introduction

Guided bone regeneration (GBR) is a current treatment for periodontal bone defects.  In the GBR technique, a barrier membrane is placed over the periodontal defect to prevent the in-growth of cells from the gingival connective tissue, epithelium, and the periodontal ligament.^1-9

GBR was used in different studies in which the purpose was bone regeneration within intra-bony defects.  This technique utilizes a mechanical barrier in an intra-bony defect with the aim of creating a secluded space to receive only cells with an osteogenic potential so osteogenesis may occur unimpeded within the space.  In an intra-osseous wound, invasion of the clot by fibroblasts can result in non-union of bone.²

If the gap surrounding an implant is large, fibrous connective tissue cells may proliferate into the area and produce a fibrous capsule around the implant.  The GBR technique may offer a method for avoiding these clinical complications.  This method has been used in periodontal surgery to develop the attachment of periodontal connective tissue to the root surface of teeth, and to exclude epithelial cells from the wound.  It has also been used to form improved osseous tissue around the implants in bone, to prevent fibrous encapsulation, and to produce additional bone in the area.⁴

In maxillofacial surgery, fibrous non-union can be an undesirable outcome, especially in extensive reconstructive surgery.  Non-union may occur when the fibroblasts organize the clot before the osseous cells migrate into the wound and initiate the bone-forming process.  It has been suggested this occurs because fibroblasts have a faster rate of migration than osteoblasts.  GBR offers a means of excluding fibroblasts from the clot; permitting slower bone-producing osteoblasts to affect clot organization and produce osseous healing.⁴

GBR membrane materials must maintain their barrier function long enough to allow osteoblasts to migrate into the wound.  The distance to be spanned determines the time the membrane must function properly.³  Resorbable and non-resorbable membranes have been used as a GBR barrier.  However, non-resorbable membranes must be surgically removed after the healing period.  A resorbable membrane that can transmit tissue fluid, but excludes undesired cells from the clot, would have the advantage of not requiring surgical removal.  Recent studies have reported the successful use of resorbable membranes in GBR.⁴

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Citation Number: Vol. 5, No. 2, Page 115