Evaluation of TiNi-based wire mesh implant for abdominal wall defect management

Abstract

Purpose. Synthetic meshes are now widely used for a repair of various tissue defects. Polypropylene meshes (PPMs), the type most frequently used for repair of abdominal wall defects, have some disadvantages, therefore the development of new mesh materials for reconstructive surgery is an important topic. A TiNi-based alloy superelastic mesh implant has been compared with a PPM in the Wistar rat model. Experimental. A midline resection abdominal wall defect (2 cm × 3 cm) was treated with a mesh implant (2.5 cm × 3.5 cm). Three groups of 20 animals were assessed: (1) a TiNi-based alloy mesh (TNM) group with the defect managed by a TiNi-based wire woven implant; (2) a PPM group with the defect repaired by Optomesh®; and (3) a no-mesh (NM) group treated without the use of any prosthetic material for systemic reaction to implant control. Evaluation of both mesh implantations was carried out on days 14, 28, 56 and 90 after surgery. The following data were compared: general condition of the animals, macroscopic evaluation of the implant area and microscopic evaluation of the tissue surrounding the mesh with the use of scanning electron and light optical microscopy. Results. All the animals from NM group developed hernias. The PPM group showed satisfactory results, although some complications like implant dislocation (6/20) and hernia recurrence (5/20) were noted. In the TNM group neither shrinkage nor implant dislocation were observed. Compared with the PPM group, the TNM group was characterized by no inflammation reaction and better integration with tissues. Conclusions. Suppression of inflammation response together with a more physiological wall remodeling process than with PPM makes TNM an attractive concept for abdominal wall defect reconstruction. Since there was neither shrinkage nor dislocation of the TNM itself it may be suitable for intraperitoneal management. The essence of enhanced biocompatibility is due to stress–strain mechanical behavior of TNM and its surface oxycarbonitride layer, which facilitate its incorporation. Summarizing, TNM was found to be a very promising material for the repair of abdominal wall defects in clinical practice. Ideally TNM would be applied in circumstances when there are indications for the management of large hernias by PPM.