Collagen membranes prevent apical migration of epithelium and support new connective tissue attachment during periodontal wound healing in dogs

Abstract

The capacity of collagen membranes to prevent the apical migration of epithelium and to support new connective tissue attachment was assessed in experimental periodontal defects in dogs. Experimental periodontal defects were produced in 8 mongrel dogs by removing the alveolar bone and the periodontal ligament over the most coronal 5 mm of the labial aspect of the maxillary canines. Experimental defects associated with the right canine and its surrounding bone were covered by collagen membranes prepared by air drying gels of rat type I fibrillar collagen. Flaps were repositioned and sutured. The contralateral control defects were sham-operated without using collagen membranes. Animals were killed, 10 and 30 days after surgery, 4 at each time point. The experimental and control sites were processed for histologic and histomorphometric evaluation. At 10 d, the average distance between the apical margin of the epithelium and the apical level of the defect (EA) sites was 3.20 +/- 0.55 mm for the experimental sites and 0.73 +/- 0.18 mm for the controls. The experimental root surfaces apical to the epithelium and the collagen membranes were covered by connective tissue cells. At 30 d, the EA for experimental and control sites were 2.55 +/- 0.36 mm and 0.47 +/- 0.30 mm, respectively. In the experimental sites healing by long junctional epithelium was observed in the coronal 40% of apico-occlusal dimension of the defect and new connective tissue attachment with inserting fibers in the apical 55% of the defect length. No new bone formation was observed. In the control sites, pocket formation was found in the most coronal one-third of the defect.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth factor delivery for oral and periodontal tissue engineering

“…Both resorbable and non-resorbable membranes have been used for these applications with comparable success, although a key advantage in the use of resorbable materials is that the need for re-entry into the regenerated site is eliminated [35,36]. Membranes derived from natural compounds (i.e., collagen) are degraded by an enzymatic process (biodegradation), catalysed by cells in the local microenvironment and within the developing tissue [37,38], but synthetic polymers (i.e., derivatives of polylactic and polyglycolic acid) are hydrolysed (bioabsorption) into the natural metabolites lactic acid and glycolic acid [39,40]. The polylactic scaffolds are popularly employed due to familiarity with their favourable biocompatible properties, which helps minimise an undesirable inflammatory response.…”

“…Two common types of polymeric materials used in growth factor delivery strategies are natural collagen-derived materials [37,38,51] and synthetic polymers of lactic and glycolic acid (i.e., poly[lactide-co-glycolide]) [40,52]. Extracellular matrix-derived macromolecules such as collagen have been used for many years in biomaterial application [53], and it is now possible to create artificial analogues of extracellular matrix proteins using recombinant DNA technology [54].…”

Pool of bovine morphogenetic proteins and guided tissue regeneration in the treatment of intrabony periodontal defects: I- Clinical measurements

“…Even though studies on GTR have evidenced formation of new attachment connective tissue, deposition of new cementum, new periodontal ligament and new bone formation in surgically created defects submitted to GTR with resorbable membrane barriers 15 , some studies reported the non-formation of new bone 16 and detected dense connective tissue instead of alveolar bone 8 after application of barriers in surgically created defects in animals. In those situations, the clinical repair of bone defects cannot be defined as regeneration, even when there is formation of new attachment connective tissue.…”

Implications of cellular and molecular biology advances in periodontal regeneration

“…The favorable biological characteristics of collagen has led to investigations on its clinical application in procedures related to periodontal regeneration. Several studies (Pitaru, 1987(Pitaru, , 1989YafTe, 1987) reported utilizing various forms of type I collagen as a membrane barrier for guided tissue regeneration procedures. Clinical human studies (Chung et al, 1990;Anderson, 1991) have also demonstrated positive results with type I collagen membranes in the treatment of periodontal defects using guided tissue regeneration techniques.…”