Achieving periodontal regeneration in class III furcation defects is challenging. Many studies have applied growth factors to periodontal defects, including fibroblast growth factors (FGFs), which demonstrate angiogenic activity and mitogenic ability. This study aimed to evaluate periodontal regeneration following the application of FGF-2 to deproteinized bovine bone mineral (DBBM) in surgically created supra-alveolar class III furcation defects of the mandibular premolars of beagles. The defects were divided into the control, DBBM, and FGF/DBBM groups. For the control group, only root planing was performed. For the DBBM group, only DBBM particles were implanted into the furcation. For the FGF/DBBM group, DBBM was soaked with 0.3% FGF-2 solution, and FGF-2/ DBBM was then positioned into the furcation. After 8 weeks, the dogs were euthanized. The micro-computed tomography analysis revealed that the changes in the bone volume of the furcation area were significantly greater in the FGF/DBBM group than in the DBBM group. In the histomorphometric analysis, the area of the newly formed bone was significantly greater in the FGF/DBBM group than in the DBBM or control group. The cementum extension was significantly longer in the FGF/DBBM or DBBM group than in the control group. The epithe...