ICE: Prevention of Cross-contamination practice questions

Answer: D) As disinfected, with the product used

• AIncorrect. Label it accurately.
• BIncorrect. That isn't needed.
• CIncorrect. Labeling prevents double handling.
• DCorrect. This tells the lab it's been treated.

Answer: D) Sterile water or sterile saline

• AIncorrect. It isn't sterile.
• BIncorrect. That isn't sterile.
• CIncorrect. It isn't sterile.
• DCorrect. Dental unit water isn't sterile.

Answer: B) Clean and disinfect it before placing it in the mouth

Dental prostheses and appliances should be cleaned and disinfected before they go to the lab and again when they come back, before placement in the patient's mouth. Treat items from the lab as contaminated unless told otherwise.

• AIncorrect. Prostheses are not sterile when they come back from the lab. Treat items received from a laboratory as contaminated unless you are told otherwise.
• BCorrect. CDC guidance says lab items should be cleaned and disinfected when they are returned and before they are placed in the patient's mouth. This protects the patient from contamination picked up at the lab or in transit.
• CIncorrect. Rinsing alone does not disinfect. The item needs cleaning and disinfection with an EPA-registered hospital disinfectant before it goes in the mouth.
• DIncorrect. Disinfection is not based on visible soil. Treat items received from the lab as contaminated and disinfect them before placement.

Answer: A) Use disposable tips or heat-sterilize reusable ones

• ACorrect. Flush the line too.
• BIncorrect. They must be sterilized or replaced.
• CIncorrect. That isn't enough.
• DIncorrect. That spreads infection.

Answer: A) Remove them with treatment gloves still on, without touching the surface beneath

Remove used surface barriers while still wearing gloves, without touching the surface beneath, and throw them away. Then remove gloves, perform hand hygiene, and put on fresh barriers for the next patient.

• ACorrect. CDC guidance says coverings are removed while the worker is still gloved and then discarded. Clean barriers go on only after the gloves come off and hands are washed. Not touching the surface underneath keeps it uncontaminated.
• BIncorrect. The used barriers are contaminated. Handling them with bare, freshly washed hands contaminates the hands. Barriers come off while gloves are still on.
• CIncorrect. Placing new barriers with the same contaminated gloves would contaminate the clean barriers. New barriers go on after the gloves are removed and hands are washed.
• DIncorrect. Surface barriers are disposable and are changed between patients. They are not disinfected and reused.

Answer: A) Place a new barrier sleeve for each patient, then inspect the wand after removal and clean and disinfect it if soiled

Treat the curing light as a clinical contact surface. Cover it with a barrier that is changed for every patient, and after removing the barrier, check the wand and clean and disinfect it if it is soiled.

• ACorrect. CDC says clinical contact surfaces, especially hard-to-clean ones, should ideally be covered with an FDA-approved barrier that is changed between patients. After the barrier is removed, check the surface and clean and disinfect it if it is contaminated.
• BIncorrect. A barrier is meant to be thrown away and replaced between patients. It is not meant to be disinfected and reused for the whole day.
• CIncorrect. Water does not disinfect. If no barrier is used, the clinical contact surface must be cleaned and then disinfected with an EPA-registered hospital disinfectant between patients.
• DIncorrect. Treating it once at the end of the day leaves it contaminated from one patient to the next. CDC also advises against using high-level disinfectants or sterilants on environmental surfaces.

Answer: A) To lower the number of oral microorganisms released in aerosols and spatter

An antimicrobial preprocedural rinse reduces the number of oral microorganisms in aerosols and spatter. It does not replace PPE or high-volume evacuation, and it has not been shown to prevent bacteremia.

• ACorrect. CDC notes that an antimicrobial preprocedural rinse can reduce the level of oral microorganisms in the aerosols and spatter produced during dental procedures. It is an added measure, not a substitute for other precautions.
• BIncorrect. CDC states that studies have shown no substantial benefit from mouth rinsing in reducing dental-induced bacteremia. Prevention of infective endocarditis is handled with antibiotic prophylaxis guidelines, not a rinse.
• CIncorrect. A rinse only reduces microbial levels. It does not eliminate them, so masks, eyewear and other PPE are still required during procedures that produce aerosols and spatter.
• DIncorrect. A mouth rinse cannot sterilize oral tissues. High-volume evacuation is still needed to reduce aerosols and spatter.

Answer: B) Supplying treatment water apart from city water

• AIncorrect. It's for water.
• BCorrect. It helps control waterline quality.
• CIncorrect. That's suction.
• DIncorrect. It's for treatment water.

Answer: A) The dental light handle

Clinical contact surfaces that are touched often and hard to clean, such as light handles, should get barriers that are changed between patients. Housekeeping surfaces such as floors, walls and sinks only need routine cleaning.

• ACorrect. CDC lists light handles as clinical contact surfaces that can be contaminated by spray, spatter or gloved hands. Because they are hard to clean, they should be covered with an FDA-cleared barrier that is changed between patients.
• BIncorrect. Floors are housekeeping surfaces. They do not touch patients or the devices used in treatment, so they are cleaned routinely rather than barrier-protected.
• CIncorrect. CDC classifies sinks as housekeeping surfaces. They are cleaned with a detergent, or disinfected if visibly contaminated with blood, but not covered between patients.
• DIncorrect. Walls are housekeeping surfaces that are not touched during care. They need routine cleaning, not barriers changed between patients.

Answer: D) 20 to 30 seconds

• AIncorrect. Flush for 20 to 30 seconds.
• BIncorrect. Flush for 20 to 30 seconds.
• CIncorrect. Flush for 20 to 30 seconds.
• DCorrect. Per CDC guidelines.