Effect of In Vitro Gingival Fibroblast Seeding on the In Vivo Incorporation of Acellular Dermal Matrix Allografts in Dogs

Abstract

Acellular dermal matrix allograft (ADMA) has been used in various periodontal procedures with successful results. Because ADMA has no blood vessels or cells, slower healing and incorporation are observed compared to a subepithelial connective tissue graft. Fibroblasts accelerate the healing process by regulation of matrix deposition and synthesis of a variety of growth factors. Thus, the objective of this study was to evaluate histologically if gingival fibroblasts affect healing and incorporation of ADMA in dogs when used as a subepithelial allograft. Gingival fibroblasts were established from explant culture from the connective tissue of keratinized gingiva collected from the maxilla of seven mongrel dogs. ADMA was seeded with gingival fibroblasts and transferred to dogs. Surgery was performed bilaterally, and the regions were divided into two groups: ADMA+F (ADMA containing fibroblasts) and ADMA (ADMA only). Biopsies were performed after 2, 4, and 8 weeks of healing. The quantity of blood vessels was significantly higher in the ADMA+F group at 2 weeks of healing (Kruskal-Wallis; P <0.05). There was no statistical difference (P >0.05) in the number of cell layers, epithelial area, or inflammatory infiltrate between the two groups at any stage of healing. The enhanced vascularization in vivo in early stages supports the important role of fibroblasts in improving graft performance and wound healing of cultured graft substitutes.