A novel characterisation approach to reveal the mechano–chemical effects of oxidation and dynamic distension on polypropylene surgical mesh (27 October 2021)

Summary

This paper in the journal RSC Advances aimed to track changes in chemical bonding taking place in PP meshes on the nanoscale via mechano–chemical processes. The authors used the novel and advanced spectroscopic characterisation technique secondary electron hyperspectral imaging (SEHI) to build high resolution chemical maps.

Polypropylene (PP) surgical mesh is associated with serious clinical complications when used in the pelvic floor for repair of stress urinary incontinence or support of pelvic organ prolapse. While manufacturers claim that the material is inert and non-degradable, there is a growing body of evidence that asserts PP fibres are subject to oxidative damage. Material surgically removed from patients suffering with clinical complications has shown some evidence of fibre cracking and oxidation. It has been proposed that a pathological cellular response to the surgical mesh contributes to medical complications, but the mechanisms that trigger the specific host response against the material are not well understood. 

The study presented key insights into the mechano–chemistry reaction of PP which can cause polymer oxidation, changes in molecular structure, crack/craze formation and the release of etched oxidised insoluble particles. SEHI, provided a new route to link the effect of localised stresses to reactions of mechano–chemistry within PP. The method of mechanical distension testing during hydrogen peroxide exposure followed SEHI image analysis could form the basis of an “early warning” system which has the ability to identify materials which are not appropriate for use as medical implants.