The influence of porosity on the integration histology of two polypropylene meshes for the treatment of abdominal wall defects in dogs

Two types of monofilament polypropylene mesh with different pore sizes, mass densities and burst strengths were used to repair two identical paired full-thickness abdominal wall defects in ten dogs, in order to compare their integration histology 90 days after implantation. On one side a standard mesh, Prolene® (Ethicon), was sutured to the borders of the defect, while on the other a new ultralightweight macroporous mesh, Mpathy® mesh, was used. There was a significantly greater densitometric proportion of mature (type I) collagen (58.38%) for Mpathy® mesh compared to Prolene® (34.05%, P = 0.01). Although Prolene® has 3.6 times the burst strength of Mpathy® mesh, the implanted tissue strength was marginally greater for Mpathy® mesh. We conclude that Mpathy® mesh gives a surgical repair that is at least as strong as that provided by Prolene®, along with a higher concentration of mature collagen and less fibrosis (P = 0.07), in this canine histology model.