7.40 Biomaterials for Hernia Repair

Implantation of foreign material has been recently recognized as providing the required tissue reinforcement for hernia surgery, overcoming initial skepticism of herniologists toward synthetic implants. Hernia meshes are currently an integral aspect of surgical techniques for the treatment of abdominal wall herniae. The first generation of synthetic meshes developed were closely knit with a pore size of >800 µm. Negative reactions associated with first generation meshes included stiffening of the abdominal wall, which caused extensive scar plates, rendering the ventral abdominal wall immobile. Modern meshes have a pore size of at least 1 mm, causing the scar to be bridged with loose connective tissue. Polymeric synthetics deployed in current procedures include polypropylene and polyester, which demonstrate required mechanical stability, low rate of accompanying inflammation, flexibility, and biocompatibility. While laparoscopic surgical procedures accompanied by mesh reinforcement reduce recurrence rates to 1–2%, disadvantages remain. These include the adhesion effect with internal organs (requiring additional nonadhesive coatings) and the impossibility of mesh implantation in an infected wound due to susceptibility of synthetic materials to bacteria because of adherence to mesh structure and formation of biofilm for immunological defense and antibiotic treatment. Biological meshes have recently been developed to overcome such difficulties.