In vitro and in vivo characterization of porcine acellular dermal matrix for gingival augmentation procedures

Background and Objective Recently, porcine acellular dermal matrix (PADM) has been proposed as a possible alternative to autogenous grafts in periodontal plastic surgery. The aim of the present study was to investigate the in vitro responses of four different oral cell lines cultured on a novel PADM. Furthermore, tissue reaction to PADM was evaluated histologically after subcutaneous implantation in mice. Material and Methods Human gingival fibroblasts (HGF), human osteoblast-like cells, human umbilical vein endothelial cells and human oral keratinocytes (HOK) were cultured and transferred on to the PADM. A tissue culture polystyrene surface served as the control. The viability of all tested cell lines on PADM was measured by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay and PrestoBlue((R)) reagent. The ToxiLight((R)) assay was performed to analyze the effect of PADM on adenylate kinase release. PADM was implanted into nude mice subcutaneously and subjected to histological analysis after 21d. Results Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assays, all tested cell lines cultured on PADM demonstrated a significant increase of viability compared to the control group (each p<0.001) with the exception of HGF and HOK after 3d (each p>0.05). According to the PrestoBlue((R)) analysis, all cell lines demonstrated a significant increase of viability compared to the control group at the particular points of measurement after 18h (HGF p<0.01; human osteoblast-like cells, human umbilical vein endothelial cells, HOK each p<0.001). No significant cytotoxic effects of PADM on the tested cell lines could be observed, as assessed by changes in adenylate kinase release. Subcutaneous implantation of PADM into nude mice demonstrated good integration with surrounding tissues and significant revascularization of its collagen structure. Conclusion Overall, the results suggest that PADM is a promising substitute for autogenous soft tissue grafts in periodontal surgery.