Comparative assessment of tissue response to a mesh implant made of polypropylene modified with carbon nanotubes and silver nanoparticles

Abstract

Treatment of abdominal hernias remains one of the most urgent problems of modern surgery. A large number of complications after hernia operations require the development of new types of implants for tissue plastic surgery. The purpose of the study is to carry out an experimental comparative assessment of tissue reaction to the implantation of the developed polypropylene mesh implant modified with carbon nanotubes and silver nanoparticles. Research was conducted on 105 sexually mature laboratory rats in three series of experiments (35 rats each). In the first series, polypropylene mesh implants were implanted in the tissues of the anterior abdominal wall, in the second – polypropylene implants coated with an antiseptic, and in the third – polypropylene implants modified with carbon nanotubes and silver nanoparticles. Animals were removed from the experiment after preliminary anesthesia 3, 5, 7, 14, 21, 30 and 90 days after the operation. The tissues of the abdominal wall were taken together with the implants, histological preparations were made, which were stained with hematoxylin and eosin and according to Van Gieson. We studied the composition and ratio of elements of cell infiltration in tissues with further statistical processing of the obtained data. It was established that during the implantation of mesh edoprostheses, regardless of their type, necrotic changes with reactive inflammation, the presence of inflammatory cell infiltrate, tissue swelling and microcirculation disorders were detected in the tissues 3-5 days after the operation. Under the condition of implantation of the developed mesh, a less pronounced exudative phase of inflammation and an earlier onset of the reparation phase were detected. Depending on the type of implant used, the subsequent reaction differed between the groups of experimental animals, which was evidenced by the regression of inflammatory phenomena in the tissues and the processes of formation of the fibrous capsule around the implants. During the implantation of nanomodified mesh implants by the 7th day of the experiment, the exudative phase of inflammation ended and the formation of a thin connective tissue capsule began, the formation of which was completed by the 21st day of observation, while when the mesh was implanted with polypropylene and polypropylene with an antimicrobial coating, the formation of the capsule lasted up to 30 days. Thus, it was established that the exudative phase of inflammation continues in the tissues around the implantation of classic polypropylene and polypropylene meshes with an antimicrobial coating up to the 14th day of the experiment, and the connective tissue capsule is formed up to the 30th day. At the same time, in the tissues around the mesh implants made of polypropylene modified with carbon nanotubes and silver nanoparticles, the exudative phase of inflammation ended by the 7th day of the experiment. This ensured the intensity of reparative regeneration processes and the separation of the implant from the surrounding tissues by a thin connective tissue capsule for up to 21 days of observation.