title: Airborne microbes in different dental environments in comparison to a public area.
abstract: OBJECTIVE
  The aim of this study was to investigate quantitatively and qualitatively the airborne microbial load in a multi-chair dental clinic, a normal dental practice and a non-dental public area over a time period of four days and at different time points to estimate the risk of infections during dental surgery.
  
  
  METHODS
  A multi-chair and a single chair treatment room each were examined in comparison to a non-medical public area over a period of four days. The colony forming units m(-3) (CFUs) were determined and isolated bacteria were characterised by morphological and biochemical analysis, gas chromatography and by 16S rRNA-gene sequencing. In the analyses enterococci were selectively searched for.
  
  
  RESULTS
  The CFUs in the multi-chair treatment room were between 20 and 1050 CFU m(-3). During treatment the maxima reached were below 800 CFU m(-3). The values in the dental practice were between 200 and 600 CFU m(-3) and remain slightly but not significantly below the levels of the clinic (p > 0.05). In the common area, the CFUs were between 200 and 800 CFU m(-3). The proportion of micrococci was 56.8% in the clinic, 56.07% in the practice and 69.67% in the public area Coagulase-negative staphylococci constituted 35% at the dental clinic, 25% at the bank and 38% at the dental practice. No significant differences amongst the units were detected in the microbial composition of their dental aerosols (p > 0.05).
  
  
  CONCLUSIONS
  Although, the bacterial counts in dental room were not significantly higher than the bacterial counts in a public area, the risk from dental clinic might be higher than a public area due to the type of micro-organisms, host susceptibility and the exposure time.
authors.affiliation: Department of Operative Dentistry and Periodontology, Albert-Ludwigs-University, Hugstetter Str. 55, D-79106 Freiburg, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Kimmerle
authors.forename: M
authors.initials: M
authors.lastname: Wiedmann-Al-Ahmad
authors.forename: K
authors.initials: K
authors.lastname: Pelz
authors.forename: A
authors.initials: A
authors.lastname: Wittmer
authors.forename: E
authors.initials: E
authors.lastname: Hellwig
authors.forename: A
authors.initials: A
authors.lastname: Al-Ahmad
mesh_terms: D000336:Aerosols; D000391:Air Microbiology; D000704:Analysis of Variance; D001419:Bacteria / Q000302:isolation & purification*; D002849:Chromatography, Gas; D015169:Colony Count, Microbial; D003428:Cross Infection / Q000517:prevention & control / Q000635:transmission; D003748:Dental Equipment / Q000382:microbiology*; D003749:Dental Facilities; D006801:Humans; D012335:RNA, Ribosomal / Q000032:analysis
chemical_list: D000336:Aerosols; D012335:RNA, Ribosomal