title: Silicon-dioxide-polyvinylpyrrolidone as a wound dressing for skin defects in a murine model.
abstract: OBJECTIVE
  There is a high demand for temporary wound dressings that improve wound healing and regeneration. Silicon (as SiO2) has been shown to support the growth and collagen formation in biological systems.
  
  
  METHODS
  A nanocomposite was made from PVP (polyvinylpyrrolidon), nano-sized silica aggregates and water and served for fabrication of a wet dressing material (SiO2-PVP gel, by cross-linking the gel) and a freeze-dried dressing material (SiO2-PVP fleece). Materials were characterized by SAXS, DSC, EDX and viscosity measurements. A 10 mm circular defect was set on both sides of the back of SKH1-hr mice (n = 40) and both dressing materials were compared with untreated controls. After 3, 6, 9, 12 and 15 days, the defect regions were explanted and evaluated by histomorphometric measurements and CD31-immunohistochemistry.
  
  
  RESULTS
  The microstructure of the compound was composed of fiber like structures. SiO2nano-aggregates inside the composite remained stable and embedded in a rigid amorphous PVP fraction. In animal experiments, all groups showed a non-irritated defect closure after 9 days. EDX of SiO2-PVP gel and fleeces revealed SiO2-PVP diffusion into the wound. Wound contraction was significantly enhanced after treatment with SiO2-PVP gel followed by SiO2-PVP fleece compared to controls. Re-epithelialization was increased in SiO2-PVP treated wounds and the regenerated epidermis showed a well-differentiated layer structure compared to untreated controls.
  
  
  CONCLUSIONS
  The results indicate that silica diffuses from the dressing into the wound. Both dressings affect the wound healing. The SiO2-based wound dressing may counteract scarring and might be suitable as a temporary wound dressing.
authors.affiliation: Department of Oral & Maxillofacial Plastic Surgery (Head: Frerich, Bernhard), University Medical Centre of Rostock, Schillingallee 35, 18057 Rostock, Germany. Electronic address: ferenc.oeri@med.uni-rostock.de.
authors.forename: Ferenc
authors.initials: F
authors.lastname: Öri
authors.affiliation: Institute for Physics (Head: Lochbrunner, Stefan), University of Rostock, Albert-Einstein-Straße 23-24, 18059 Rostock, Germany. Electronic address: richard.dietrich@uni-rostock.de.
authors.forename: Richard
authors.initials: R
authors.lastname: Dietrich
authors.affiliation: Institute for Physics (Head: Lochbrunner, Stefan), University of Rostock, Albert-Einstein-Straße 23-24, 18059 Rostock, Germany. Electronic address: cornelia.ganz@uni-rostock.de.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Ganz
authors.affiliation: Department of Oral & Maxillofacial Plastic Surgery (Head: Frerich, Bernhard), University Medical Centre of Rostock, Schillingallee 35, 18057 Rostock, Germany. Electronic address: michael.dau@med.uni-rostock.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Dau
authors.affiliation: Department of Oral & Maxillofacial Plastic Surgery (Head: Frerich, Bernhard), University Medical Centre of Rostock, Schillingallee 35, 18057 Rostock, Germany. Electronic address: daniel.wolter@med.uni-rostock.de.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wolter
authors.affiliation: Department of Oral & Maxillofacial Plastic Surgery (Head: Frerich, Bernhard), University Medical Centre of Rostock, Schillingallee 35, 18057 Rostock, Germany. Electronic address: annika.kasten@med.uni-rostock.de.
authors.forename: Annika
authors.initials: A
authors.lastname: Kasten
authors.affiliation: Institute for Physics (Head: Lochbrunner, Stefan), University of Rostock, Albert-Einstein-Straße 23-24, 18059 Rostock, Germany. Electronic address: thomas.gerber@uni-rostock.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gerber
authors.affiliation: Department of Oral & Maxillofacial Plastic Surgery (Head: Frerich, Bernhard), University Medical Centre of Rostock, Schillingallee 35, 18057 Rostock, Germany. Electronic address: bernhard.frerich@med.uni-rostock.de.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Frerich
mesh_terms: D000818:Animals; D001458:Bandages; D062109:Dermatologic Surgical Procedures / Q000379:methods*; D051379:Mice; D008812:Mice, Hairless; D053761:Nanocomposites / Q000627:therapeutic use; D011205:Povidone / Q000627:therapeutic use*; D012822:Silicon Dioxide / Q000627:therapeutic use*; D014783:Viscosity
chemical_list: D012822:Silicon Dioxide; D011205:Povidone
keywords: Angiogenesis; Epithelialization; Regeneration; SiO(2) polymer; Wound healing