Periodontal tissue engineering by nano beta-tricalcium phosphate scaffold and fibroblast growth factor-2 in one-wall infrabony defects of dogs

Background and Objective: Nanoparticle bioceramics are being investigated for biomedical applications. We fabricated a regenerative scaffold comprising type I collagen and beta-tricalcium phosphate (beta-TCP) nanoparticles. Fibroblast growth factor-2 (FGF-2) is a bioeffective signaling molecule that stimulates cell proliferation and wound healing. This study examined the effects, on bioactivity, of a nano-beta-TCP/collagen scaffold loaded with FGF-2, particularly on periodontal tissue wound healing. Material and Methods: Beta-tricalcium phosphate was pulverized into nanosize particles (84 nm) and was then dispersed. A nano-beta-TCP scaffold was prepared by coating the surface of a collagen scaffold with a nanosize beta-TCP dispersion. Scaffolds were characterized using scanning electron microscopy, compressive testing, cell seeding and rat subcutaneous implant testing. Then, nano-beta-TCP scaffold, nano-beta-TCP scaffold loaded with FGF-2 and noncoated collagen scaffold were implanted into a dog one-wall infrabony defect model. Histological observations were made at 10 d and 4 wk post-surgery. Results: Scanning electron microscopy images show that TCP nanoparticles were attached to collagen fibers. The nano-beta-TCP scaffold showed higher compressive strength and cytocompatibility compared with the noncoated collagen scaffold. Rat subcutaneous implant tests showed that the DNA contents of infiltrating cells in the nano-beta-TCP scaffold and the FGF-2-loaded scaffold were approximately 2.8-fold and 3.7-fold greater, respectively, than in the collagen scaffold. Histological samples from the periodontal defect model showed about five-fold greater periodontal tissue repair following implantation of the nano-beta-TCP scaffold loaded with FGF-2 compared with the collagen scaffold. Conclusion: The beta-TCP nanoparticle coating strongly improved the collagen scaffold bioactivity. Nano-beta-TCP scaffolds containing FGF-2 are anticipated for use in periodontal tissue engineering.