title: Influence of implantation interval on the long-term biocompatibility of surgical mesh.
abstract: BACKGROUND
  The aim was to study the long-term tissue response to polypropylene mesh.
  
  
  METHODS
  This was a retrieval study that investigated 76 polypropylene meshes with a median implantation interval of 18 (range 2-180) months. Mesh was explanted following hernia recurrence, infection or pain. The median implantation interval was 20 (range 4-180) months in the recurrence group, 30 (range 5-48) months in the pain group and 10 (range 2-56) months in the infection group (P < 0.05, infection versus pain or recurrence). The inflammatory response was determined by immunohistochemistry of macrophages (CD68), polymorphonuclear granulocytes (CD15) and T and B lymphocytes (CD3 and CD20). The cell turnover within the interface mesh fibre-recipient tissue was measured by TUNEL for apoptosis or DNA strand breaks, Ki67 for cell proliferation and heat-shock protein (HSP) 70 for cell stress.
  
  
  RESULTS
  With the exception of HSP-70, levels of all variables decreased over time. Sex, age, type of previous operation or location of the mesh did not have a significant influence.
  
  
  CONCLUSIONS
  Long-term incorporated polypropylene mesh in humans has a more favourable tissue response with increasing implantation interval.
authors.affiliation: Institute of Pathology, German Centre of Excellence for Biomaterial and Implant Pathology, Interdisciplinary Centre of Clinical Science BIOMAT, Rhenish Westfalian Technical High School-Aachen, Aachen, Germany. klosterhalfen@pat.rwth-aachen.de
authors.forename: B
authors.initials: B
authors.lastname: Klosterhalfen
authors.forename: K
authors.initials: K
authors.lastname: Junge
authors.forename: B
authors.initials: B
authors.lastname: Hermanns
authors.forename: U
authors.initials: U
authors.lastname: Klinge
mesh_terms: D000328:Adult; D000906:Antibodies / Q000032:analysis; D001672:Biocompatible Materials; D005260:Female; D006547:Hernia / Q000276:immunology / Q000473:pathology; D059685:Herniorrhaphy; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D011126:Polypropylenes / Q000276:immunology / Q000627:therapeutic use*; D012008:Recurrence; D013526:Surgical Mesh
chemical_list: D000906:Antibodies; D001672:Biocompatible Materials; D011126:Polypropylenes