title: An evaluation of microbiologic contamination on phosphor plates in a dental school.
abstract: OBJECTIVE
  The objective of this study was to determine if phosphor plates used in predoctoral clinics are microbiologically contaminated and to identify the source of contamination.
  
  
  METHODS
  Forty-five of 300 phosphor plates (15%) were randomly selected for examination. The plates were pressed into individual blood agar plates, were incubated using standard techniques at 37 degrees C, and were monitored for 72 hours. The number, size, distribution, and variety of resulting colonies were noted. A representative of each type of colony was selected to be Gram stained using the standard technique.
  
  
  RESULTS
  Of the plates, 42.2% were uncontaminated, 57.8% yielded bacterial colonies, and 15.6% of those colonies demonstrated hemolytic growth. The hemolytic growth included combined alpha and beta hemolysis and beta only hemolysis. Six colonies were gram-positive rods and 7 were gram-positive cocci.
  
  
  CONCLUSIONS
  Meticulous infection-control techniques are inevitable and continuous reinforcement and training for staff and students are mandatory. Periodic gas sterilization of phosphor plates may be necessary.
authors.affiliation: Oral Health and Diagnostic Sciences, School of Dentistry, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912-1241, USA. skalathingal@mail.mcg.edu
authors.forename: Sajitha Menon
authors.initials: SM
authors.lastname: Kalathingal
authors.forename: Stephanie
authors.initials: S
authors.lastname: Moore
authors.forename: Soon
authors.initials: S
authors.lastname: Kwon
authors.forename: George S
authors.initials: GS
authors.lastname: Schuster
authors.forename: Michael K
authors.initials: MK
authors.lastname: Shrout
authors.forename: Kevin
authors.initials: K
authors.lastname: Plummer
mesh_terms: D015169:Colony Count, Microbial; D003740:Dental Clinics; D004866:Equipment Contamination; D006095:Gram-Positive Cocci / Q000302:isolation & purification; D016987:Gram-Positive Rods / Q000302:isolation & purification; D006801:Humans; D019552:Infection Control, Dental / Q000379:methods; D019252:Radiography, Dental, Digital / Q000295:instrumentation*; D013242:Sterilization / Q000379:methods; D013291:Streptococcus / Q000302:isolation & purification; D014963:X-Ray Intensifying Screens / Q000382:microbiology*