• Login
    View Item 
    •   Home
    • Theses and Dissertations
    • Theses and Dissertations
    • View Item
    •   Home
    • Theses and Dissertations
    • Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of TUScholarShareCommunitiesDateAuthorsTitlesSubjectsGenresThis CollectionDateAuthorsTitlesSubjectsGenres

    My Account

    LoginRegister

    Help

    AboutPeoplePoliciesHelp for DepositorsData DepositFAQs

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    EVALUATION OF A RAPID BIOLOGICAL SPORE ASSURANCE TEST FOR DENTAL INSTRUMENT STERILIZATION

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Lee_temple_0225M_14492.pdf
    Size:
    958.4Kb
    Format:
    PDF
    Download
    Genre
    Thesis/Dissertation
    Date
    2021
    Author
    Lee, Andie Hyunkyung
    Advisor
    Rams, Thomas E.
    Committee member
    Page, Lawrence
    Whitaker, Eugene J.
    Department
    Oral Biology
    Subject
    Dentistry
    Health sciences
    Biological indicator
    Biological spore tests
    Geobacillus stearothermophilus
    Steam autoclave
    Sterilization
    Permanent link to this record
    http://hdl.handle.net/20.500.12613/6549
    
    Metadata
    Show full item record
    DOI
    http://dx.doi.org/10.34944/dspace/6531
    Abstract
    Objectives: Dental instrument sterilization with steam autoclaves is critical to maintaining infection control standards in dental practice, and preventing patient-to-patient transmission of pathogenic bacteria and viruses. The American Dental Association and the United States Centers for Disease Control and Prevention recommend, and many state dental laws require, weekly use of biological spore tests to verify dental instrument sterilization outcomes. However, the most widely used biological spore test needs microbial culture incubation for 2 days after autoclave exposure, which limits swift identification of sterilization failure. To address this issue, this study evaluated the reliability of a new rapid biological spore test for determining the sterilization efficacy of dental steam autoclaves within 20 minutes. Methods: Two commercial biological spore tests were evaluated in Temple University dental school steam autoclaves, 1.) the Steris Celerity 20 Steam Biologic Indicator with a 20-minute outcome time requirement, and 2.) the 3M Attest 1262 Biological Indicator with a 48-hour outcome time requirement. Both biological spore tests employed live thermoresistant Geobacillus stearothermophilus spores as an indicator of whether sterilization conditions in steam autoclaves were met or not. To compare their efficacy, a total of 157 pairs of the two biological spore tests were placed into dental steam autoclaves with dental instrument cassettes, and subjected to manufacturer-recommended steam autoclave temperature and air pressure operating conditions for an adequate sterilization time of 15 minutes. Two additional groups of 10 pairs each of the two biological indicators were subjected to appropriate steam autoclave temperature and air pressure settings, but only for aborted non-sterilizing time periods of 10 and 5 minutes, respectively. Subsequent aseptic processing and laboratory incubation of both biological indicators was initiated within 2-24 hours, and followed manufacturer recommendations. After autoclave exposure, Steris Celerity 20 Steam Biologic Indicator test ampoules were incubated in a specialized instrument for 20 minutes at 57 °C, which also spectrophotometrically evaluated the microbial culture medium for fluorescent α- glucosidase enzyme signal changes. No change in fluorescent intensity represented successful sterilization, whereas increased fluorescence indicated survival of viable G. stearothermophilus spores germinating into vegetative bacterial cells after failed sterilization. 3M Attest 1262 Biological Indicator ampoules were incubated for 48 hours in a laboratory heating block at 57 °C, after which a pH-based color change in the microbial culture broth was visually assessed. No change in the color of the culture broth (purple color remains) indicated successful sterilization, whereas development of a yellow color in the culture broth, as a result of viable G. stearothermophilus spore germination into vegetative bacterial cells, denoted failed sterilization. Results: A total of 354 biological indicators were exposed to dental steam autoclaves sterilization cycles, incubated for either 20 minutes or 48 hours, and evaluated for G. stearothermophilus spore growth. The Steris Celerity and 3M Attest biological spore tests both uniformly detected successful sterilization, with no G. stearothermophilus spore growth, after 15 minutes of steam autoclave exposure at manufacturer recommended steam autoclave temperature and air pressure operating conditions. This provided 100% agreement, and no statistically significant difference in the prevalence of successful sterilization outcomes, between 157 pairs of both biological indicator types after 15 minutes of steam autoclave exposure. Similarly, both biological spore test systems were also in complete agreement after only 5 minutes of steam autoclave exposure, with 100% of both biological indicators positive for G. stearothermophilus spore growth, indicating failed sterilization. In contrast, after 10 minutes of steam autoclave exposure, there was a complete lack of agreement between the two types of biological indicators. All 10 Steris Celerity spore tests were positive, whereas all 10 3M Attest ampoules were negative, for G. stearothermophilus spore growth after 10 minutes of steam autoclave exposure. Relative to this disagreement, a non-biological chemical indicator strip that was part of the Steris biological indicator test system failed to have a darkened bar develop and extend into the “Accept (OK)” portion of the strip for all Steris Celerity spore tests exposed to either 5 minutes or 10 minutes of steam autoclave exposure, indicating that adequate autoclave steam, temperature and/or time parameters had not been attained for sterilization. Conclusions: The Steris Celerity biological spore test was successful in rapidly determining the sterilization efficacy of dental steam autoclaves within only a 20-minute incubation time period, as compared to 48 hours of incubation required by the widely-used 3M Attest biological spore test. As a result, this rapid assay offers earlier detection of steam autoclave sterilization failure before potentially contaminated dental instruments are used in clinical patient care. The alarming failure of 3M Attest biological spores to grow after a non-sterilizing 10-minute steam autoclave exposure time warrants further product evaluation.
    ADA compliance
    For Americans with Disabilities Act (ADA) accommodation, including help with reading this content, please contact scholarshare@temple.edu
    Collections
    Theses and Dissertations

    entitlement

     
    DSpace software (copyright © 2002 - 2022)  DuraSpace
    Temple University Libraries | 1900 N. 13th Street | Philadelphia, PA 19122
    (215) 204-8212 | scholarshare@temple.edu
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.