chapter 21

  1. classification of patient care  or what are the three instrument classifications that are used to determine the method of sterilization?
    • 1. Critical
    • 2. semicritical
    • 3. noncritical
  2. Critical Function
    touch bone or penetrate soft tissue
  3. critical examples
    • surgical and other instruments used to penetrate soft tissue or bone
    • including forceps
    • scalpels
    • bone chisel
    • scalers
    • burs
  4. semicritical function
    touch mucous membranes but will not touch bone or penetrate soft tissue
  5. semicritical examples
    • mouth mirrors
    • amalgam condensers
    • plastic-handled brushes
    • high-volume evacuator tips
    • rubber dam forceps
    • x-ray film holders
  6. noncritical function
    contact only with intact skin
  7. noncritical examples
    • external dental x-ray head (PID)
    • the lead apron
    • curing light that comes into contact only with intact skin
  8. CDC guidelines for sterilization and disinfection of patient care items
    • Use only U.S. Food and Drug Administration (FDA)Cleared medical devices for sterilization(autoclave)
    • Reprocess heat sensitive critical and semicritical instruments by using FDA cleared sterilants/high level disinfectants or an FDA cleared low temperature sterilization method .
  9. Personal Protective Equipment (always use PPE when processing instruments) or what PPE is necessary when one is processing instruments?
    • utility gloves
    • mask
    • eyewear
    • protective clothing
  10. Exposure can occur through
    • percutaneous injury (needle sticks or cuts)
    • by contact with the mucous membranes of the eyes, nose or mouth
  11. instrument-processing area or sterilization area
    should be centrally located in the office to allow easy access from all patient care areas.

    this minimizes the need to cary contaminated items through clean areas of the office, where sterilized instruments, fresh disposable supplies and prepared trays are stored.
  12. "ideal" instrument processing area
    • should be dedicated only to instrument processing
    • should be physically separated from the operatories and the dental laboratory
    • should not be a part of a common walkway
  13. what is the basic rule of the workflow pattern in an instrument processing area?
    proceed in a single loop, from dirty, to clean, to sterile, to storage, without ever doubling back
  14. contaminated area
    • the initial receiving area (they are held for processing)
    • disponsable items not already discarded int he treatment room are removed from the instrument tray and disposed of as contaminated waste.
    • cleaning should be done before all disinfection and sterilization processes
  15. contaminated area contains
    • clean protective eyewear and utility gloves
    • counter space
    • a sink
    • a waste disposal container
    • holding solution
    • ultrasonic cleaner
    • eyewash station
    • supplies for wrapping instruments before sterilization
  16. name the 3 methods of precleaning instruments
    • hand scrubbing
    • ultrasonic cleaning
    • instrument washing machines
  17. if instruments cannot be processed immediately, what should be done with them?
    place in a holding solution to prevent the drying of blood and debris on the instruments
  18. Holding solutions Facts
    may be any noncorrosive liquid.

    container must have a lid and be labeled with both a bio-hazard label (because of the contaminated instruments) and  a chemical label (because of the cleaner/detergent)

    should be changed at least twice daily, and more frequently if it becomes clouded.
  19. which method of precleaning instruments is least desirable?
    hand scrubbing because it requires direct hand contact with the contaminated instrument
  20. Ultrasonic cleaners
    • Used to loosen and remove debris from instruments.
    • reduce the risk of hand injury from cuts and punctures that occur during the cleaning process.
    • works by producing sound waves beyond the range of human hearing
  21. Ultrasonic cleaning solution
    • do not use other chemicals such as plain disinfectants in the ultrasonic
    • unit should be labeled with both chemical label and biohazard label because it contains a chemical and contaminated instruments
  22. care of the ultrasonic cleaner
    • solution is highly contaminated and must be discard at least once a day or sooner if it becomes visibly cloudy
    • when solution is changed, the inside of the pan and the lid should be rinsed with water,disinfected, rinsed again and dried
    • all PPE should be worn while one is changing solutions in the ultrasonic cleaner
  23. testing ultrasonic cleaner
    • hold a 5 x 5 inch sheet of lightweight aluminum foil vertically (like a curtain) half submerged in the fresh, unused solution
    • run the unit for 20 seconds, then hold the foil up toward the light
  24. packaging materials
    • self sealing or heat sealed "poly" bags or tubes provide an excellent wrap
    • paper wraps
    • cloth wraps
  25. Types of Sterilization
    • steam sterilization
    • dry heat sterilizers
    • unsaturated chemical vapor
  26. sterilization of unwrapped instruments
    • called flash sterilization
    • used to sterilize unwrapped patient care items for immediate use
    • should be used only under certain conditions
  27. CDC guidelines for sterilization of unwrapped
    critical instruments that were sterilized unwrapped should not be stored unwrapped and semicritical instruments
  28. sterilization
    destroys all microbial forms, including bacterial spores.
  29. sterile
    an absolute term; there is no partially sterile or almost sterile
  30. What are the most common forms of heat sterilization?
    • steam sterilization
    • chemical vapor sterilaztion
    • dry heat sterilization
  31. liquid sterilant
    is not recommend for use on any item that can withstand heat sterilization or is disposable
  32. steam autoclave
    used to sterilize dental instruments and other items by means of steam under pressure

    its heat that kills the microorganisms not the pressure
  33. 4 cycles of autoclaves
    • heatup cycle
    • sterilizing cycle
    • depressurization cycle
    • drying cycle
  34. steps for autoclave
    • check solution level
    • timing sterilization cycle
  35. advantage of autoclave
    short time
  36. disadvantage of autoclave
    • damages some plastic and rubber items
    • requires use of distilled water
    • may rust non stainless steel instruments and burs
  37. flash sterilization
    • refers to sterilizing unpackaged instruments with the use of short exposure times
    • the disadvantaged is that unwrapped instruments are no longer sterile once they are removed from the sterilizer and before they are used on the next patient
    • should be used only for instruments that are to be used promptly upon removal from the sterilizer
  38. unsaturated chemical vapor sterilization
    similar to autoclave, except that a combination of chemicals (alcohol, formaldehyde, ketone, acetone)

    • OSHA requieres a material safey data sheet (MSDS) on the chemical vapor solution because of the toxicity of the chemicals
  39. advantages of chemical vapor
    • does NOT rust, dull or corrode dry metal instruments
    • short time
    • good penetration of steam
  40. disadvantages of chemical vapor
    • damages some plastic and rubber items
    • requires special solution
    • requires good ventilation (filter) vapors can leave an unpleasant odor in the area and may be irritating to the eyes
  41. 3 major factors involved in chemical vapor sterilization
    • pressure, which should measure 20 psi
    • temperature, should measure 270f (131C)
    • time, should  measure 20 to 40 min
  42. dry heat sterilization
    • operates at approximately 320 to 375f
    • 60 min
  43. advantages of dry heat
    no corrosion, no rust
  44. disadvantaged of dry heat
    • long sterilization time
    • damages some plastic and rubber items
  45. 2 types of dry heat
    • static : similar to an oven (1 to 2 hrs)
    • forced air : rapid heat transfer sterilizers (12 min)
  46. ethylene oxide sterilization
    • use more in hospitals
    • requires 4 to 12 hours
    • is ineffective on wet items
    • toxicity is a risk if the gas is not handled properly
  47. liquid chemical sterilants
    sterilization in glutaraldehyde requires a 10 hours contact time; anything shorter than 10 hours is disinfection, not sterilization
  48. sterilizing instruments with liquid chemical sterilants
    • to prepare solution:
    • use utility gloves, mask, eyewear, and protective clothing when preparing, using and discard the solutions(liquid sterilatns are highly toxic and can lead to respiratory problems)
    • prepare solution for use as a sterile. label containers with name of the chemical, date of preparation and any other information that relates to the hazards of this products(brand remain active for 30 days; others may have a longer or shorter life)
    • cover the container and keep it closed unless you are putting instruments in or taking them out (glutaraldehyde produces toxic fumes)

    • use the solution
    • preclean, rinse, and dry items to be processed
    • rinse items with water, and dry. place items in clean package.

    sterility is best maintain by rising with sterile water, drying with sterile towel, and placing in a sterile container

    cant verify with spores test
  49. what causes sterilization failure?
    • improper instrument cleaning
    • packaging
    • sterilizer malfunction
    • improper timing
    • improper tempeture
    • improper loading
  50. monitoring service
    • positive result: sterilization did not occur
    • negative result: sterilization occur (cultures read at 24,48, and 72 hours)
  51. what are the 3 forms of sterilization monitoring?
    physical: looking at the gauges and readings on the sterilizer and recording the temperature, pressure and exposure time

    chemical: (external and internal) involves the use of a heat sensitive chemical that changes color when exposed to certain conditions

    biologic: spore testing, the only way to determine whether sterilization has occurred and to confirm that all bacteria and endospores have been killed. CDC,ADA, and OSAP recommended weekly biologic monitoring of sterilization equipment
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chapter 21
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