Comparison between polypropylene and polyethylene terephthalate (Dacron) meshes for abdominal wall hernia repair: a chemical and morphological study

For the first time, by scanning electron microscopy (SEM) polypropylene (PP) excised meshes for abdominal wall hernia repair, ethylene oxide sterilized, have been shown to be greatly damaged physically, independently of the implantation time, while the polyethylene terephthalate (PET) or Dacron ones, gamma radiation sterilized, did not undergo alterations due to the sterilization process and were not damaged, even after long implantation periods. Fourier - Transform Infrared Spectroscopy (FTIR) study of PP and PET excised meshes, as well as of their extracts with cyclohexane, has shown the presence of species such as squalene, palmitic and stearic acid, in some cases, cholesterol transferred from the surrounding tissues to the polymer during the implantation period. In the case of PP meshes, these small organic molecules would reduce physical and mechanical properties of the material. A hypothesis is presented to account for the better behavior (not in the clinical sense) of PET meshes.