title: Foam pore size is a critical interface parameter of suction-based wound healing devices.
abstract: BACKGROUND
  Suction-based wound healing devices with open-pore foam interfaces are widely used to treat complex tissue defects. The impact of changes in physicochemical parameters of the wound interfaces has not been investigated.
  
  
  METHODS
  Full-thickness wounds in diabetic mice were treated with occlusive dressing or a suction device with a polyurethane foam interface varying in mean pore size diameter. Wound surface deformation on day 2 was measured on fixed tissues. Histologic cross-sections were analyzed for granulation tissue thickness (hematoxylin and eosin), myofibroblast density (α-smooth muscle actin), blood vessel density (platelet endothelial cell adhesion molecule-1), and cell proliferation (Ki67) on day 7.
  
  
  RESULTS
  Polyurethane foam-induced wound surface deformation increased with polyurethane foam pore diameter: 15 percent (small pore size), 60 percent (medium pore size), and 150 percent (large pore size). The extent of wound strain correlated with granulation tissue thickness that increased 1.7-fold in small pore size foam-treated wounds, 2.5-fold in medium pore size foam-treated wounds, and 4.9-fold in large pore size foam-treated wounds (p < 0.05) compared with wounds treated with an occlusive dressing. All polyurethane foams increased the number of myofibroblasts over occlusive dressing, with maximal presence in large pore size foam-treated wounds compared with all other groups (p < 0.05).
  
  
  CONCLUSIONS
  The pore size of the interface material of suction devices has a significant impact on the wound healing response. Larger pores increased wound surface strain, tissue growth, and transformation of contractile cells. Modification of the pore size is a powerful approach for meeting biological needs of specific wounds.
authors.affiliation: Boston and Cambridge, Mass.; Lausanne, Switzerland; and Erlangen, Germany From the Division of Plastic Surgery, Brigham and Women's Hospital, Harvard Medical School; the Department of Plastic Surgery, University Hospital Lausanne; the School of Engineering and Applied Sciences, Harvard University; and the Max-Planck-Institute for the Science of Light.
authors.forename: Yvonne I
authors.initials: YI
authors.lastname: Heit
authors.forename: Pouya
authors.initials: P
authors.lastname: Dastouri
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Helm
authors.forename: Giorgio
authors.initials: G
authors.lastname: Pietramaggiori
authors.forename: George
authors.initials: G
authors.lastname: Younan
authors.forename: Paolo
authors.initials: P
authors.lastname: Erba
authors.forename: Stefan
authors.initials: S
authors.lastname: Münster
authors.forename: Dennis P
authors.initials: DP
authors.lastname: Orgill
authors.forename: Sandra S
authors.initials: SS
authors.lastname: Scherer
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011140:Polyurethanes; D016062:Porosity; D013396:Suction / Q000295:instrumentation; D014945:Wound Healing
chemical_list: D011140:Polyurethanes; C028279:polyurethane foam
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