Cross Infection and Microbiology Flashcards
What is direct cross infection?
Direct contact with a contaminated person (sneezing, physical contact)
What is indirect cross infection?
Not having direct contact with the person (contaminated instruments)
What is disinfection?
Destruction of most microorganisms, but not spores and certain viruses
Advantages of disinfection
Useful for work surfaces and other non-sterilisable items
Disadvantages of disinfection
Doesn’t achieve sterilisaton and the products often do not have a long shelf life
What is sodium hypochlorite used for?
On non-metal surfaces as it can corrode metal or cause staining on materials
What is chlorhexidine gluconate used for?
Used in hibiscrub hand wash and corsodyl mouthwash
What is isopropyl alcohol used for?
For dental chairs, work surface and general disinfection
Why can isopropyl alcohol not be used as an instrument cleaner?
It can bind blood proteins to steel
What is sterilisation?
The destruction of all microorganisms including spores
How can sterilisation be achieved?
Using an autoclave, hot air oven, glass bead sterilisation or industrial sterilisation
How does an autoclave work?
Steam from distilled water is put under pressure
What are the hold values for an autoclave?
2-3 bar of pressure for a minimum of 3 minutes at 134 degrees ceclius.
What is an N type autoclave?
Non-vacuum
What is an S type autoclave?
Specialist autoclave
What is a B type autoclave?
Vacuum
When would glass bead sterilisation be used?
For endodontic files between stages on the same patient.
What type of radiation is used for industrial sterilisation?
Gamma radiation
What is industrial sterilisation used for?
Sterilising single use items.
What is the best method of cross infection prevention?
Single use items