Accelerating effects of basic fibroblast growth factor on wound healing of rat palatal mucosa

Purpose: In this study, basic fibroblast growth factor (bFGF) was examined for its ability to accelerate tissue repair in a rat oral mucosal wound. Materials and Methods: A 4-mm mucosal defect was surgically made to the depth of the periosteum in a rat palate. bFGF was injected along the edge of the mucosal defect immediately after surgery. A control group received only phosphate-buffered saline vehicle. Results: bFGF significantly accelerated granular tissue formation and reepithelialization. From the histologic analysis, the bFGF-treated group showed relatively faster collagen maturation. Starting 3 days after surgery, fibroblast growth factor receptor 1 (FGFR1)-positive cells appeared in the granular and spinous cell layers of the reepithelializing mucosa in the bFGF-treated group, whereas almost none was observed in the intact oral mucosa. By day 5, FGFR1-positive cells were seen below the stratum corneum, even in the control group. However, the number and intensity of FGFR1-positive cells in the bFGF-treated group were greater than in the control group. Results of immunostaining against proliferating cell nuclear antigen showed that bFGF stimulated cell proliferation of the basal cell layer in the regenerating epithelium. At a higher dose of bFGF, proliferating cell nuclear antigen-positive cells were also observed in the submucosal connective tissue. Conclusion: By the induction of its ligand protein concomitant with direct effects such as increased granular tissue formation and reepithelialization, a single topical application of bFGF facilitated wound heating in rat oral mucosa. The results of this study support the consideration for bFGF application for patients with impaired healing of oral mucosal injury. (C) 2004 American Association of Oral and Maxillofacial Surgeons.