BDNF/Hyaluronic Acid Enhances Periodontal Tissue Regeneration

Objectives: Brain-derived neurotrophic factor (BDNF), one of the neurotrophin family, affects neural development, survival and repair. Furthermore, BDNF is involved with hard tissue regeneration. We have already revealed that BDNF/atelocollagen complex enhanced periodontal tissue regeneration in vivo. However,°@it is necessary to investigate a safer carrier for clinical application of BDNF. In this study, we evaluated the efficacy of synthesized high molecular weight hyaluronic acid gel (HA) as a BDNF carrier.

Methods: The class III furcation defects were created surgically at the second, third and fourth premolars (P2, P3 and P4) in female beagle dogs. The cementum faced to the defects was removed and then impression materials were placed in the defects to induce inflammation. BDNF (5µg, 50µg, 500µg and 2mg/ml)/HA complex was applied into the defects. For a negative control, only HA was applied. Six weeks after the application, periodontal tissue regeneration was evaluated by histological and morphometric analyses.

Results: In BDNF/HA groups, the denuded root surface was almost completely covered with new cementum and the periodontal ligament separated the regenerated bone from the cementum with an adequate width. However, complete alveolar bone reconstruction was not obtained at six weeks after the application. Epithelial cell invasion, bone ankylosis and root resorption were not observed at all. In the negative control group, epithelial cells invaded into the top of the furcation and cementum regeneration was not observed within the area. Less bone regeneration was observed in this group than in the BDNF/HA groups. Morphometrical analyses showed that BDNF, especially at 5 and 50 µg/ml, significantly increased new cementum length and new bone area.

Conclusion: The combination of BDNF and hyaluronic acid gel may have high potential for periodontal tissue regeneration in clinical usage.