Comparison of meshes for the repair of experimental abdominal wall defects.

The aim of this experimental study was to compare the effects of polytetrafluoroethylene patch, polypropylene mesh, and porcine dermal collagen implant in rats for the repair of abdominal wall defects. We created experimental abdominal wall defects in 45 rats (three groups of fifteen) and repaired them with polytetrafluoroethylene, polypropylene mesh, and porcine dermal collagen implant by onlay technique. We sacrificed 4 rats from each group at 4, 8, 10, and 12 weeks after implantation and observed if hernia, adhesion, effusion, or infection occurred. We measured the tensile strengths of meshes by a digital tensometer. We made histological and electron microscopic evaluations of the meshes. Postoperative infection and effusion occurred in one rat in each group. Hernia was not found throughout the trial. The tensile strength of polytetrafluoroethylene patch and polypropylene mesh increased more than porcine dermal collagen implant until the end of week 12. Adhesion formation was minimal in the porcine dermal collagen group and moderate in the polytetrafluoroethylene patch and polypropylene mesh groups. Polytetrafluoroethylene patch showed minimum absorption and maximum foreign body reaction. Our results show that although none of the material reached the criteria of ideal mesh, polypropylene mesh is the better mesh for the repair of abdominal defects. Polytetrafluoroethylene patch though expensive, can also be used as a reliable mesh. We do not advise porcine dermal collagen implant as a mesh for abdominal defects due to its weak structure.