ADEX Dental Hygiene Infection Control Principles Questions and Answers — Questions and Answers
Question 1: Which of the following methods provides the ultimate verification of sterilization success by directly challenging the sterilization process?
- Observing the external chemical indicator tape for a color change.
- Checking the sterilizer's physical readouts for correct time, temperature, and pressure.
- Using a biological indicator (spore test) on a weekly basis. (Correct answer)
- Placing an internal chemical indicator strip in each package.
Correct answer: Using a biological indicator (spore test) on a weekly basis.
Biological indicators, or spore tests, are the most accepted method for monitoring the sterilization process because they directly assess the procedure's effectiveness at killing the most resistant microorganisms, such as Geobacillus stearothermophilus. While mechanical and chemical indicators are crucial for routine monitoring of each load, they only show that certain physical conditions were met, not that sterilization was actually achieved.
Question 2: A dental hygienist sustains a percutaneous injury with a contaminated scaler. After performing immediate first aid by washing the wound with soap and water, what is the required NEXT step according to the OSHA Bloodborne Pathogens Standard?
- Go to an urgent care clinic for post-exposure prophylaxis.
- Insist that the source patient undergo immediate blood testing.
- Complete an incident report at the end of the workday.
- Report the exposure incident to the employer or designated supervisor. (Correct answer)
Correct answer: Report the exposure incident to the employer or designated supervisor.
According to OSHA's Bloodborne Pathogens Standard, after immediate first aid, the exposure incident must be reported immediately to the employer. This action initiates the required post-exposure evaluation and follow-up protocol, which the employer is responsible for providing at no cost to the employee. This protocol includes documenting the incident, evaluating the source patient (with consent), and providing confidential medical counseling and testing for the employee.
Question 3: Which of the following actions during instrument reprocessing represents a critical error that could lead to sterilization failure?
- Placing clean, but still damp, instruments into a sterilization pouch. (Correct answer)
- Using an ultrasonic cleaner with the lid in place.
- Wearing puncture-resistant utility gloves while cleaning instruments.
- Storing sterile packages in a closed, dry cabinet.
Correct answer: Placing clean, but still damp, instruments into a sterilization pouch.
Instruments must be completely dry before being packaged for heat sterilization. Any residual moisture can interfere with the sterilization process and may cause wet packs, which can wick microorganisms through the packaging material after the cycle is complete, compromising the sterility of the instruments.
Question 4: According to CDC guidelines, a clinical contact surface (e.g., a light handle) that is visibly contaminated with blood must be cleaned and then treated with which type of disinfectant?
- A low-level hospital disinfectant.
- A high-level disinfectant/sterilant like glutaraldehyde.
- An intermediate-level disinfectant with a tuberculocidal claim. (Correct answer)
- An antiseptic hand rub with at least 60% alcohol.
Correct answer: An intermediate-level disinfectant with a tuberculocidal claim.
For clinical contact surfaces visibly contaminated with blood, the CDC recommends cleaning followed by disinfection with an EPA-registered hospital disinfectant that has a tuberculocidal claim (i.e., an intermediate-level disinfectant). The ability to kill Mycobacterium tuberculosis demonstrates a disinfectant's potency against a broad range of pathogens. Low-level disinfectants are for surfaces not contaminated with blood, and high-level disinfectants are for heat-sensitive semi-critical items.
Question 5: A hygienist is preparing for a procedure that will generate significant aerosols. What is the correct sequence for donning (putting on) the required Personal Protective Equipment (PPE)?
- Gloves, Gown, Mask, Eye Protection
- Gown, Mask, Eye Protection, Gloves (Correct answer)
- Mask, Eye Protection, Gloves, Gown
- Eye Protection, Gloves, Gown, Mask
Correct answer: Gown, Mask, Eye Protection, Gloves
The CDC recommends donning PPE in an order that moves from the body core outwards, finishing with the hands. The correct sequence is: first the gown, followed by the mask or respirator, then goggles or a face shield, and finally, gloves. Gloves are donned last so they can be pulled over the cuffs of the gown, creating a secure barrier.
Question 6: The foundational concept of Standard Precautions, as defined by the CDC, is based on which of the following principles?
- Treating all human blood and certain body fluids as if they are known to be infectious for bloodborne pathogens. (Correct answer)
- Applying extra infection control measures only for patients with a documented infectious disease.
- Using Transmission-Based Precautions for all patient encounters in a dental setting.
- Requiring hand hygiene only when gloves are torn or hands are visibly soiled.
Correct answer: Treating all human blood and certain body fluids as if they are known to be infectious for bloodborne pathogens.
The core principle of Standard Precautions is to treat all human blood, body fluids, secretions, excretions (except sweat), non-intact skin, and mucous membranes as if they are infectious for pathogens like HIV, HBV, and others. This approach applies to all patients, regardless of their diagnosis or presumed infection status, ensuring a consistent level of safety for every encounter.
ADEX Dental Hygiene Infection Control Principles Questions and Answers
Which of the following methods provides the ultimate verification of sterilization success by directly challenging the sterilization process?