Title: Effectiveness of Various Decontamination Methods on CAD/CAM Mirror Sleeves
Jonathan Kruze (Presenter)
Lori Henrichs, USAF
Kelli Mack, USAF
Kraig Vandewalle, USAF
Objectives: CAD/CAM camera sleeves that are exposed to the oral cavity must be properly processed after use to prevent cross contamination. The purpose of this study was to evaluate the effectiveness of several methods of disinfection and sterilization of CAD/CAM camera mirror sleeves (Omnicam, Sirona).
Methods: The outer surface of seven groups of mirror sleeves were inoculated by submerging them in suspensions of Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 15442 for 5 minutes. Post inoculation, the groups were decontaminated as follows. Group A: no decontamination or sterilization following inoculation (positive control). Group B: surface cleaning with neutral soap (Dawn Dish Soap, Procter and Gamble) and water only. Group C: surface disinfection with 17% isopropanol (CaviWipes, Metrex). Groups D-F received a different high-level disinfection (HLD) solution in the HLD container (Sirona) as follows: Group D: 0.55% ortho-phthaladehyde (CIDEX OPA, Johnson & Johnson). Group E: 7.5% hydrogen peroxide (Sporox II, Sultan). Group F: 7.35% hydrogen peroxide and 0.23% peracetic acid (Compliance, Metrex). Group G received dry-heat sterilization (RAPIDHEAT Sterilizer, Cox). Also, dry-heat sterilized mirror sleeves which were not exposed to bacteria or disinfected served as a negative control. Each group was tested with 3 cycles of 3 sleeves each (n=9). The presense of bacteria was tested on the outside of the sleeves by plating samples on TSA II, with incubatation at 35+2°C ambient air for 24 hours. A percent reduction in CFU/mL from the positive control group was determined per group.
Results: All methods of disinfection except Dawn Dish Soap resulted in greater than 99.99% reduction in CFU/mL compared to the positive control group.
Conclusions: Both high-level disinfection or dry-heat sterilization resulted in no growth of microorganisms in cultures taken from the surface of the bacterial-contaminated mirror sleeves.