title: An investigation of the decontamination of Siqveland matrix bands.
abstract: OBJECTIVE
  This study investigated blood contamination of artificially and clinically contaminated Siqveland matrix bands and retainers. A modified version of the recognised Kastle-Meyer test for blood was used to compare the efficacy of enzymatic agents, a washer-disinfector and an instrument washer for pre-sterilisation cleaning of Siqveland matrix bands and retainers.
  
  
  METHODS
  Assembled Siqveland matrix bands were contaminated either artificially with horse blood or clinically during dental treatment. Contaminated assembled matrix bands and retainers were subjected to immersion in an enzymatic agent, automated processing in a washer-disinfector or instrument washer, or a combination of pre-soaking and automatic cleaning. Residual blood contamination from each band and retainer was measured and compared to the volume of blood recovered from an unprocessed control group of contaminated assembled matrix bands or retainers.
  
  
  RESULTS
  Residual blood was recovered from every clinically contaminated assembled Siqveland matrix band and retainer. The volume of blood recovered from assembled Siqveland matrix bands ranged from 0.13-7.1 microl and from retainers, following removal of the matrix band, from 0.001-1.523 microl. The most effective method of pre-sterilisation cleaning for artificially contaminated assembled matrix bands was processing in the washer-disinfector. Conversely, the most effective method for cleaning clinically contaminated assembled matrix bands and retainers was pre-soaking in an enzymatic agent followed by a heavy-duty cycle in an instrument washer.
  
  
  CONCLUSIONS
  It is not possible to clean assembled Siqveland matrix bands using any method currently available to dental practitioners. Matrix bands should be discarded after use on one patient. Once the band is removed, all detectable blood can be removed from the retainer by pre-soaking in an enzymatic detergent followed by processing in an instrument washer.
authors.affiliation: Hoghton Street Dental Practice, 22 Hoghton Street, Southport, UK. cwblackadder@btinternet.com
authors.forename: C L
authors.initials: CL
authors.lastname: Whitworth
authors.forename: K
authors.initials: K
authors.lastname: Davies
authors.forename: N O A
authors.initials: NO
authors.lastname: Palmer
authors.forename: M V
authors.initials: MV
authors.lastname: Martin
mesh_terms: D000818:Animals; D001769:Blood; D003666:Decontamination / Q000379:methods*; D019551:Dental Disinfectants; D003902:Detergents; D004203:Disinfection / Q000295:instrumentation / Q000379:methods; D004798:Enzymes; D004866:Equipment Contamination / Q000517:prevention & control; D006736:Horses; D019552:Infection Control, Dental / Q000379:methods*; D016910:Orthodontic Brackets; D018704:Orthodontic Retainers
chemical_list: D019551:Dental Disinfectants; D003902:Detergents; D004798:Enzymes