Application of the BFGF and β-TCP complex to peri-implant bone defects in dogs

Abstract

A bone substitute, beta-tricalcium phosphate, was combined with a basic fibroblast growth factor to create a fibroblast growth factor/tricalcium phosphate complex. This complex was then implanted into canine mandibles to evaluate the usefulness of this treatment in bony defects around dental implants. Four beagles received implants that were installed into fresh extraction sockets of third and fourth mandibular premolars. All surgical procedures were performed under general anesthesia with intravenous sodium thiopental. Gingival incisions were performed mesially from the second premolar and distally to molars. Full-thickness buccal and lingual flaps were raised. After vertical interradicular sectioning, each root was carefully elevated and then gently extracted. Buccal bone defects adjacent to extraction sockets with a height of 7 mm and 3 mm in the mesio-distal direction were created on third and fourth premolars, respectively, using round burs with sterile saline irrigation. These defects were then assigned to the control, fibroblast growth factor, tricalcium phosphate complex, or fibroblast growth factor/tricalcium phosphate group. Animals were sacrificed 4 weeks after surgery. Tissue blocks were fixed in 4% paraformaldehyde and then scanned with micro-computed tomography before sectioning for light microscopy. New bone height and bone mineral density in sites were significantly larger in tricalcium phosphate and fibroblast growth factor than in tricalcium phosphate groups. New bone height was also significantly larger in tricalcium phosphate and fibroblast growth factor/tricalcium phosphate groups than in fibroblast growth factor and control groups. These results indicate that fibroblast growth factor/tricalcium phosphate complex is useful as a growth factor carrier and scaffold for bone augmentation around dental implants.