IMPAIRED EARLY BONE-FORMATION IN PERIODONTAL FENESTRATION DEFECTS IN DOGS FOLLOWING APPLICATION OF INSULIN-LIKE GROWTH-FACTOR-(II) - BASIC FIBROBLAST GROWTH-FACTOR AND TRANSFORMING GROWTH-FACTOR-BETA-1

Effects of a topically applied growth factor combination on fibroblast migration, collagen fiber formation and bone regeneration were studie d in standardized periodontal defects in 4 beagle dogs. Following elev ation of facial mucoperiosteal flaps, fenestration defects, 3 mm in di ameter, were made through the cortical bone and into the dentin of max illary and mandibular teeth. Collagen sponges, impregnated with 200 ng insulin-like growth factor II, 20 ng basic fibroblast growth factor a nd 6 ng transforming growth factor beta 1 were fitted to defects rando mly in right or left quadrants and the flaps repositioned and sutured. Contralateral control defects received the collagen with vehicle only . Experimental procedures were staggered to allow observations of heal ing 3, 7, 10, and 14 days after surgery. Histometric analysis showed n o differences in fibroblast and collagen density between control and g rowth factor defects. Bone regeneration was significantly greater in c ontrol than in growth factor defects 10 and 14 days after surgery. The rate of healing generally appeared more affected by intra-dog variati ons or procedural variations than by the growth factor combination.