Evaluation of synthetic reticular hybrid meshes designed for intraperitoneal abdominal wall repair: Preclinical and in vitro behavior

The reticular structure of a mesh limits the formation of a continuous mesothelial monolayer in vitro, regardless of its composition. The presence of titanium as a coating or polyvinylidene fluoride interwoven with polypropylene in a reticular structure did not prevent adhesions. The hybrid meshes showed proper integration and an increase in the mRNA Col 1 levels in the implant area compared to Surgipro or Preclude.

The mesothelialization capacity of TiMESH and DynaMesh was evaluated in vitro and compared to that of Surgipro (reticular bare polypropylene) and Preclude (laminar expanded polytetrafluoroethylene). Mesh fragments were placed on the intact parietal peritoneum of New Zealand white rabbits (n = 24), and laparoscopy performed 7 days post-surgery. Fourteen days post-implantation, adhesions were evaluated and host tissue incorporation, macrophage response, collagen expression (immunohistochemistry/RT-PCR) and neoperitoneum formation assessed. Adhesions and omental tissue were also examined.

Mesh pores in reticular meshes were devoid of cells in the in vitro study. TiMESH, DynaMesh and Surgipro showed similar adhesion rates at 7/14 days and optimal tissue integration, with significant differences in comparison to Preclude. The greatest presence of macrophages was observed for TiMESH and was significant versus that for Preclude. Hybrid meshes revealed significantly higher collagen 1 mRNA expression in implants, with no differences in the levels of collagen 3. Omental samples from animals with a reticular mesh showed significantly greater collagen 1 mRNA levels. Conclusions: The reticular structure of a mesh limits the formation of a continuous mesothelial monolayer in vitro, regardless of its composition. The presence of titanium as a coating or polyvinylidene fluoride interwoven with polypropylene in a reticular structure did not prevent adhesions. The hybrid meshes showed proper integration and an increase in the mRNA Col 1 levels in the implant area compared to Surgipro or Preclude.