NBDHE NBDHE Infection Control and Sterilization 1 — Questions and Answers
Question 1: Which type of instrument requires sterilization according to the Spaulding classification for 'critical' items?
- Instruments that contact mucous membranes only
- Instruments that penetrate soft tissue or bone (Correct answer)
- Items that touch only intact skin
- Environmental surfaces in the operatory
Correct answer: Instruments that penetrate soft tissue or bone
Critical items penetrate soft tissue or bone and must be sterile to prevent transmission of any microorganism.
Question 2: The standard gravity displacement autoclave operates at which temperature and duration for wrapped instruments?
- 212°F (100°C) for 20 minutes
- 250°F (121°C) for 15-30 minutes (Correct answer)
- 270°F (132°C) for 3-4 minutes
- 320°F (160°C) for 60 minutes
Correct answer: 250°F (121°C) for 15-30 minutes
Gravity displacement autoclaves operate at 121°C (250°F) at 15 psi for 15-30 minutes to achieve sterilization of wrapped instruments.
Question 3: Which bloodborne pathogen poses the GREATEST transmission risk per needlestick exposure in the dental setting?
- HIV
- Hepatitis C virus (HCV)
- Hepatitis B virus (HBV) (Correct answer)
- Hepatitis A virus (HAV)
Correct answer: Hepatitis B virus (HBV)
HBV has a needlestick transmission rate of 6-30%, far exceeding HCV at 1.8% and HIV at 0.3%.
Question 4: According to standard precautions, gloves must be changed:
- Every 30 minutes during patient care
- Between patients and when torn or punctured (Correct answer)
- Only when visibly contaminated with blood
- At the end of each clinical session
Correct answer: Between patients and when torn or punctured
Standard precautions require glove changes between each patient and immediately if gloves are torn or punctured during care.
Question 5: Which item is classified as 'semicritical' in the Spaulding classification system?
- Surgical scalpel blade
- Dental chair armrest
- Reusable impression tray (Correct answer)
- Lead apron used for radiography
Correct answer: Reusable impression tray
Reusable impression trays contact mucous membranes without penetrating tissue, classifying them as semicritical items requiring sterilization or high-level disinfection.
Question 6: What level of disinfection is required for clinical contact surfaces in the dental operatory?
- Sterilization
- High-level disinfection
- Intermediate-level disinfection (Correct answer)
- Low-level disinfection
Correct answer: Intermediate-level disinfection
Clinical contact surfaces require intermediate-level disinfection using an EPA-registered hospital disinfectant with a tuberculocidal claim.
Question 7: OSHA's Bloodborne Pathogens Standard requires employers to offer hepatitis B vaccination to:
- All employees regardless of job duties
- Employees with potential occupational exposure to blood or OPIM (Correct answer)
- Only licensed dental professionals
- Employees only after a documented exposure incident
Correct answer: Employees with potential occupational exposure to blood or OPIM
OSHA requires hepatitis B vaccination be offered at no cost to all employees with potential occupational exposure to blood or other potentially infectious materials (OPIM).
NBDHE NBDHE Infection Control and Sterilization 1
Which type of instrument requires sterilization according to the Spaulding classification for 'critical' items?