title: Oral, intestinal, and skin bacteria in ventral hernia mesh implants.
abstract: BACKGROUND
  In ventral hernia surgery, mesh implants are used to reduce recurrence. Infection after mesh implantation can be a problem and rates around 6-10% have been reported. Bacterial colonization of mesh implants in patients without clinical signs of infection has not been thoroughly investigated. Molecular techniques have proven effective in demonstrating bacterial diversity in various environments and are able to identify bacteria on a gene-specific level.
  
  
  OBJECTIVE
  The purpose of this study was to detect bacterial biofilm in mesh implants, analyze its bacterial diversity, and look for possible resemblance with bacterial biofilm from the periodontal pocket.
  
  
  METHODS
  Thirty patients referred to our hospital for recurrence after former ventral hernia mesh repair, were examined for periodontitis in advance of new surgical hernia repair. Oral examination included periapical radiographs, periodontal probing, and subgingival plaque collection. A piece of mesh (1×1 cm) from the abdominal wall was harvested during the new surgical hernia repair and analyzed for bacteria by PCR and 16S rRNA gene sequencing. From patients with positive PCR mesh samples, subgingival plaque samples were analyzed with the same techniques.
  
  
  RESULTS
  A great variety of taxa were detected in 20 (66.7%) mesh samples, including typical oral commensals and periodontopathogens, enterics, and skin bacteria. Mesh and periodontal bacteria were further analyzed for similarity in 16S rRNA gene sequences. In 17 sequences, the level of resemblance between mesh and subgingival bacterial colonization was 98-100% suggesting, but not proving, a transfer of oral bacteria to the mesh.
  
  
  CONCLUSIONS
  The results show great bacterial diversity on mesh implants from the anterior abdominal wall including oral commensals and periodontopathogens. Mesh can be reached by bacteria in several ways including hematogenous spread from an oral site. However, other sites such as gut and skin may also serve as sources for the mesh biofilm.
authors.affiliation: Department of Gastroenterologic Surgery, Akershus University Hospital, University of Oslo, Lørenskog, Norway.|Faculty of Medicine, University of Oslo, Oslo, Norway; odd.langbach@ahus.no.
authors.forename: Odd
authors.initials: O
authors.lastname: Langbach
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Anne Karin
authors.initials: AK
authors.lastname: Kristoffersen
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Emnet
authors.initials: E
authors.lastname: Abesha-Belay
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Morten
authors.initials: M
authors.lastname: Enersen
authors.affiliation: Department of Gastroenterologic Surgery, Akershus University Hospital, University of Oslo, Lørenskog, Norway.|Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Ola
authors.initials: O
authors.lastname: Røkke
authors.affiliation: Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Ingar
authors.initials: I
authors.lastname: Olsen
keywords: 16S rRNA; DNA; implants; mesh; oral bacteria; ventral hernia