title: Prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in the oral cavity.
abstract: OBJECTIVE
  To assess the prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus (MRSA) in plaque and tongue samples from systemically healthy subjects with periodontal health, gingivitis or chronic periodontitis.
  
  
  METHODS
  After screening 720 potentially eligible subjects, 154 systemically healthy participants were ultimately enrolled in the current study. Subgingival samples were taken from the first molars and the tongue and analyzed for the presence of S. aureus and MRSA by polymerase chain reaction (PCR), using primers and conditions previously described in the literature. In addition, samples were taken from deep periodontal pockets of chronic periodontitis patients. Statistical analysis was performed by applying non-parametric tests (Kruskal-Wallis for clinical parameters, and z-test with Bonferroni corrections for distributions of assessed parameters). All comparisons were set at the 0.05 significance level.
  
  
  RESULTS
  S. aureus was detected in 18% of all participants and in 10% of the samples tested. No significant differences were found in its distribution among the three investigated groups (z-test for proportions with Bonferroni corrections, p>0.05). The mecA gene was not present in any of the S. aureus found.
  
  
  CONCLUSIONS
  S. aureus can be found in the oral environment regardless of the periodontal conditions and therefore should be considered as a member of the transient flora not participating in periodontal pathology. Subgingival sites and tongue surfaces seem to be an unusual habitat of MRSA.
authors.affiliation: 251 General Air Force Hospital, Athens, Greece. Electronic address: gkoukos1977@gmail.com.
authors.forename: Georgios
authors.initials: G
authors.lastname: Koukos
authors.affiliation: Department of Preventive Dentistry, Periodontology and Implant Biology, Dental School, Aristotle University of Thessaloniki, Greece.
authors.forename: Dimitra
authors.initials: D
authors.lastname: Sakellari
authors.affiliation: Department of Genetics and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, Greece.
authors.forename: Minas
authors.initials: M
authors.lastname: Arsenakis
authors.affiliation: Department of Preventive Dentistry, Periodontology and Implant Biology, Dental School, Aristotle University of Thessaloniki, Greece.
authors.forename: Lazaros
authors.initials: L
authors.lastname: Tsalikis
authors.affiliation: Department of Mechanical Engineering, Aristotle University of Thessaloniki, Greece.
authors.forename: Theodora
authors.initials: T
authors.lastname: Slini
authors.affiliation: Department of Preventive Dentistry, Periodontology and Implant Biology, Dental School, Aristotle University of Thessaloniki, Greece.
authors.forename: Antonios
authors.initials: A
authors.lastname: Konstantinidis
mesh_terms: D055113:Chronic Periodontitis / Q000382:microbiology*; D003430:Cross-Sectional Studies; D003773:Dental Plaque / Q000382:microbiology; D005260:Female; D005891:Gingivitis / Q000382:microbiology*; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D009055:Mouth / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D014059:Tongue / Q000382:microbiology
keywords: Antimicrobial drug resistance; Methicillin-resistant Staphylococcus aureus; Molecular biology; Polymerase chain reaction; Staphylococcus aureus