ADEX Infection Control Principles 5 — Questions and Answers
Question 1: Which method of sterilization is recommended for heat-sensitive dental instruments that cannot withstand autoclave temperatures?
- Dry-heat oven at 160°C
- Ethylene oxide gas or low-temperature hydrogen peroxide plasma sterilization (Correct answer)
- Boiling water immersion for 30 minutes
- Intermediate-level liquid chemical disinfection
Correct answer: Ethylene oxide gas or low-temperature hydrogen peroxide plasma sterilization
Heat-sensitive items require low-temperature sterilization technologies such as ethylene oxide or hydrogen peroxide plasma, as boiling and chemical disinfection do not achieve sterilization.
Question 2: What is the significance of the term 'standard precautions' replacing 'universal precautions' in infection control terminology?
- Standard precautions apply only to blood, not other body fluids
- Standard precautions expand protection to all body fluids, secretions, and excretions except sweat, regardless of visible blood (Correct answer)
- Standard precautions are less stringent than universal precautions
- Standard precautions only apply to HIV-positive patients
Correct answer: Standard precautions expand protection to all body fluids, secretions, and excretions except sweat, regardless of visible blood
Standard precautions broadened universal precautions to include all moist body substances except sweat, recognizing that non-bloody body fluids can also transmit pathogens.
Question 3: A dental hygienist with a latex allergy should request which alternative glove material that provides similar barrier protection?
- Vinyl gloves for all procedures
- Nitrile gloves, which provide comparable barrier protection without latex allergens (Correct answer)
- Polyethylene gloves for aerosol-generating procedures
- Double latex gloves to reduce allergen contact
Correct answer: Nitrile gloves, which provide comparable barrier protection without latex allergens
Nitrile gloves offer excellent barrier protection, durability, and chemical resistance without natural rubber latex proteins that trigger Type I hypersensitivity reactions.
Question 4: During aerosol-generating dental procedures, which respiratory protection provides the highest level of protection for the dental hygienist?
- Standard surgical mask
- N95 filtering facepiece respirator fitted and fit-tested (Correct answer)
- Cloth face covering with filter insert
- Dust mask rated P100
Correct answer: N95 filtering facepiece respirator fitted and fit-tested
An N95 respirator, when properly fit-tested, filters at least 95% of airborne particles and provides significantly more protection than a surgical mask during aerosol generation.
Question 5: Instrument packaging that shows wet or torn pouches after sterilization should be:
- Used immediately since sterilization already occurred
- Re-sterilized in new packaging after re-cleaning (Correct answer)
- Opened carefully and items used if not visibly contaminated
- Stored separately and used within 24 hours
Correct answer: Re-sterilized in new packaging after re-cleaning
Wet or compromised packaging indicates a breach in sterility; instruments must be reprocessed from the cleaning step in new intact packaging before use.
Question 6: According to the Spaulding classification, mouth mirrors fall into which category and require what minimum level of processing?
- Critical — sterilization
- Semicritical — sterilization or high-level disinfection (Correct answer)
- Non-critical — intermediate-level disinfection
- Non-critical — low-level disinfection
Correct answer: Semicritical — sterilization or high-level disinfection
Mouth mirrors contact mucous membranes and are classified as semicritical, requiring sterilization when possible or, at minimum, high-level disinfection.
Question 7: What is the correct action if a dental waterline quality test reveals bacterial counts exceeding 500 CFU/mL?
- Continue using the unit since counts above 500 only affect immunocompromised patients
- Shock-treat the waterlines with an approved disinfectant protocol and retest before patient use (Correct answer)
- Flush the lines for 30 seconds before each patient and retest at the next scheduled interval
- Report the result to the state dental board immediately
Correct answer: Shock-treat the waterlines with an approved disinfectant protocol and retest before patient use
The CDC recommends that dental unit water meet the EPA drinking water standard of ≤500 CFU/mL; counts exceeding this require corrective treatment (shocking) and retesting before resuming patient care.
ADEX Infection Control Principles 5
Which method of sterilization is recommended for heat-sensitive dental instruments that cannot withstand autoclave temperatures?