Preparation and in vivo investigation of oligomeric proanthocyanidins cross-linked collagen serving as synthesized tissue regeneration membrane.

In this study, type I collagen membranes were prepared using oligomeric proanthocyanidins (OPCs) as the cross-linking agent. The fabricated materials were evaluated to be applied as guided tissue regeneration membranes for periodontal defects. The mechanical strength of the cross-linked collagen membranes, namely OPCs-Col films, using different concentrations of OPCs ranged from 30 to 60 kPa. The cross-linked collagen membranes had better thermal stability than non-cross-linked one and could effectively resist the decomposition in collagenase solution as long as fifty days. The results of material characterization showed that 10% OPCs-Col film was ideal for our purpose. In vitro study using L929 and MG-63 cells revealed that 10% OPCs-Col film had great biocompatibility while OPC was demonstrated to be not cytotoxic as glutaraldehyde and genipin but even promote L929 cells. The material was further studied for in vivo studies with two models, subcutaneous and cranium defects in rat. The subcutaneous test showed that the regeneration membrane degraded till one month and the inflammatory response also reduced with implantation time. When implanted into the cranium defect, no lesions of the brain were caused and new bone tissue was observed inside the material. The results of in vivo studies showed that the synthesized membrane was helpful for tissue regeneration with long degradation time. The tissue regeneration membranes can barrier the rapid growing soft tissue, in order to save the capacity for the growth of neo bone.