During incorporation, the filaments are enclosed by an internal and external granuloma. When filament distance is too small, there is a risk that the whole intervening space will be filled with scar tissue (closed pores). Sufficiently large pores can prevent this.
How is this prevented? PP implants must have a pore diameter of at least 1 mm in all directions, even under load! In the case of PVDF implants, a diameter of 0.6 mm is already sufficient to keep the pores open due to the lower granuloma thickness. Only in this way can local autochthonous tissue form through a pore [6,8].
Textile porosity refers to the permeable component of a mesh implant before the body has reacted to it.
Effective porosity refers to the permeable component of a mesh implant after the body has reacted to it.
Rule of Thumb:
A ‘pore’ less than 1 mm in diameter is closed by the body with scar tissue
= 0% effective porosity