Microorganisms
What is a microorganism that can cause disease called?
A pathogen.
How many links are in the chain of infection?
Six.
What is the term for disease transmission through physical contact with an infected person?
Direct transmission.
What does PPE stand for?
Personal protective equipment.
What process destroys all microorganisms, including bacterial spores?
Sterilization.
What should happen to reusable instruments after they are used on a patient?
They must be cleaned and processed appropriately before reuse.
What does DUWL stand for?
Dental unit waterlines.
What type of waste includes regular office garbage that is not contaminated with blood or other potentially infectious material?
General waste.
What does SDS stand for?
Safety Data Sheet.
What type of microorganism requires a living host cell to reproduce?
A virus.
What is the term for the place where a microorganism lives and multiplies?
A reservoir.
What type of transmission occurs when someone touches a contaminated surface and then touches their mouth?
Indirect transmission.
Who should be treated using Standard Precautions?
Every patient.
What is the purpose of precleaning a contaminated surface?
To remove visible debris and organic material before disinfection.
What type of instrument penetrates soft tissue or contacts bone?
A critical instrument.
What is biofilm?
A layer of microorganisms that attaches to a surface and is protected by a slimy coating.
Where should used needles and other contaminated sharp items be discarded?
In an approved sharps container.
What is the purpose of an SDS?
To provide information about a hazardous product, including its hazards, safe handling, storage, and emergency procedures.
What protective structure allows certain bacteria to survive harsh conditions?
A bacterial spore.
What is the difference between a portal of exit and a portal of entry?
A portal of exit is how a microorganism leaves its source. A portal of entry is how it enters a new host.
What type of exposure occurs when contaminated blood or saliva enters the body through a needle-stick injury?
A percutaneous exposure.
Name four types of PPE commonly used during dental procedures.
Gloves, a mask, protective eyewear or a face shield, and protective clothing.
A dental assistant wipes away visible blood, then wipes the surface again and allows it to remain wet for the required contact time. What do the two steps accomplish?
The first wipe precleans the surface. The second wipe disinfects it.
How should a reusable critical instrument be processed?
It must be sterilized.
Why do dental unit waterlines allow bacteria to grow more easily than regular faucets?
Their narrow tubing, slow water flow, and periods of stagnant water encourage biofilm formation.
A cotton roll is saturated with blood and would release blood if squeezed. How should it be classified?
Infectious waste.
What does a hazard pictogram communicate?
The type of hazard associated with a chemical or product.
What does viral specificity mean?
A virus attaches to and infects particular types of host cells that have compatible receptors.
What is a fomite? Give one dental office example.
A contaminated object that can transmit microorganisms, such as a dental instrument, light handle, or countertop.
Name three routes through which infectious microorganisms can enter a dental healthcare worker’s body.
Through the eyes, nose, mouth, broken skin, or a puncture injury.
What type of gloves should be worn when handling contaminated instruments or cleaning treatment rooms?
Utility Gloves.
What is the difference between disinfection and sterilization?
Disinfection destroys many disease-causing microorganisms but does not necessarily destroy bacterial spores. Sterilization destroys all microorganisms, including spores.
What is a transfer surface?
A surface touched by contaminated hands or instruments during patient care, such as a light handle or dental chair control.
What is backflow?
The reverse flow of contaminated fluids into dental equipment or waterlines.
How should an extracted tooth without amalgam be classified?
Infectious waste.
What is the purpose of a signal word on a chemical label?
To indicate the seriousness of the hazard. Common signal words are “Danger” and “Warning.”
What is the difference between gram-positive and gram-negative bacteria?
Gram-positive bacteria retain the primary stain and appear purple. Gram-negative bacteria do not retain the primary stain and appear pink or red.
Name all six links in the chain of infection.
Infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host.
What are two ways to break the chain of infection in a dental office?
Examples include performing hand hygiene, wearing PPE, disinfecting surfaces, sterilizing instruments, and receiving recommended immunizations.
A dental assistant removes their gloves after treating a patient. What must they do next?
Perform hand hygiene.
What test uses bacterial spores to determine whether a sterilizer is working properly?
A biological indicator test, also called a spore test.
How should transfer surfaces be managed between patients?
Remove and replace protective barriers, or clean and disinfect the surfaces between patients.
Why is flushing dental unit waterlines alone not enough to remove biofilm?
Flushing may reduce loose microorganisms temporarily, but it does not reliably remove the biofilm attached to the inside of the tubing.
Why must a tooth containing an amalgam restoration be handled differently from a tooth without amalgam?
Because amalgam contains mercury and requires appropriate hazardous waste handling.
Name four common hazard communication label elements.
A pictogram, signal word, hazard statement, and precautionary statement.