A Pilot Study Evaluating the Effect of Recombinant Human Bone Morphogenetic Protein‐2 and Recombinant Human Beta‐Nerve Growth Factor on the Healing of Class III Furcation Defects in Dogs

Abstract

The quantity of regenerated bone induced by recombinant human bone morphogenetic protein-2 (rhBMP2) is encouraging, but sometimes the quality is inferior. Recombinant human beta-nerve growth factor (rh beta-NGF) plays a major role in bone remodeling. This study evaluates the quality and quantity of regenerated bone in periodontal regeneration following topical application of the two growth factors to Class III furcation defects. Thirty-six inflamed Class III furcation defects were created in six beagle dogs at sites of mandibular premolars 2, 3, and 4, and then biodegradable hydrogel incorporating rhBMP2 and rh beta-NGF was topically applied to the defects. The groupings were as follows: G1, untreated (control group A); G2, carrier alone (control group B); G3, 0.4% rhBMP2 + carrier; G4, 2% rh beta-NGF + carrier; G5, 0.4% rhBMP2 + 2% rh beta-NGF + carrier; and G6, 0.2% rhBMP2 + 1% rh beta-NGF + carrier. Eight weeks after application, the quality and quantity of regenerated tissue were evaluated by scanning electron microscopy observation, calcium/phosphorus ratio analysis, and histologic evaluation. The regenerated bone in G5 exhibited the highest calcium/phosphorus ratio among all groups and showed a denser structure with more calcified substances on the collagen fiber surface than that in the other groups. Histomorphometric analysis revealed that 0.4% rhBMP2 + 2% rh beta-NGF promoted the highest percentage of periodontal regeneration among all groups. The results of this pilot study suggest that a topical application of rhBMP2 and rh beta-NGF may improve the quality and quantity of regenerated bone in artificially created Class III furcation defects of beagle dogs.