Aim: Recombinant human growth/differentiation factor-5 (rhGDF-5) is being evaluated as a candidate therapy in support of periodontal regeneration. The objective of this study was to evaluate cementum and alveolar bone formation, and aberrant healing events following surgical implantation of rhGDF-5 in an absorbable collagen sponge (ACS) carrier using an established periodontal defect model.
Materials and methods: Bilateral 4 x 5 mm (width x depth), one-wall, critical-size, intrabony periodontal defects were surgically created at the mandibular second and fourth pre-molar teeth in 15 Beagle dogs. Five animals received 1 microg/defect and five animals 20 microg/defect rhGDF-5 in unilateral defect sites. Contralateral sites received treatments reported elsewhere. Five animals received rhGDF-5/ACS with 0 (buffer control) and 100 microg/defect rhGDF-5 in contralateral defect sites. The animals were euthanized at 8 weeks post-surgery for histologic and histometric evaluation.
Results: Surgical implantation of rhGDF-5 stimulated significant periodontal regeneration. Cementum formation was significantly enhanced in sites implanted with rhGDF-5 (1 and 100 microg) compared with control (p<0.05). Similarly, bone formation height was significantly greater in sites receiving rhGDF-5 (1 and 100 microg) compared with control (p<0.05). There were no significant or remarkable differences in bone and cementum formation within the selected dose interval (1, 20 and 100 microg rhGDF-5). None of the control or the rhGDF-5 sites exhibited root resorption, ankylosis, or other aberrant tissue reactions.
Conclusion: Surgical implantation of rhGDF-5/ACS may be used safely to support periodontal wound healing/regeneration in intrabony periodontal defects without complications.