Theory 1 Ch. 4 infection control: clinical procedures instrument recirculation/sterilization

all materials EXCEPT oils, waxes, powders, and materials that are impervious to steam

• by heat and moisture
• (pressure only attains high temp)

• steam
• (air must not be present)

• 121 degrees c (250 f)
• 15 minutes (30 min heavy load)
• 15 psi

• Dry = open door to release steam pressure, dries for 15 min
• Liquids = reduce pressure slowly over 10-12 minutes to prevent boiling escape or fluids into the chamber

• fast and efficient
• many materials may be treated
• most economical method of sterilization

• may corrode instruments
• not used for oils, powders, or waxes

oxidation

• objects that cannot undergo the steam autoclave (oils, powders)
• burs that may corrode can be placed in dry heat

• heat that is conducted from the exterior surface to the interior of the object
• must reach peak temp
• any oil, grease, or debris will keep instruments from proper sterilization and act as an insulating agent

• temp: 160 c (320 f)
• time: maintained for two hours
• 170 c (340 f)
• time: maintained for one hour
• NO PRESSURE!
• (timing starts AFTER temp has been reached)

• for materials that cannot undergo steam pressure
• well suited for sharp instruments (if not exceeding 160 c)
• no corrosion

• long exposure time
• maintain high temp

alcohols, formaldehyde, ketone, water, acetone heated under pressure producing a gas that is a sterilizing agent

• not for materials altered by chemicals, heat sensitive, low melting plastics, liquids or heat sensitive handpieces i.e. bite block
• chemical and pressure penetrate the object

• 127 - 132 c (260 f - 270 f)
• 20 to 40 pounds pressure
• minimum 20 minutes after temp and pressure have been attained
• longer time for heavier loads

• dry
• need short time to cool

• corrosion/rust free
• short cycle
• easy to operate and care for (refill every 30 cycles)

• ventilation needed in room, not a small one
• odor
• tightly wrapped, heavy or sealed packages will not permit penetration of formaldehyde and alcohol vapors

• inactivation of essential cellular proteins or enzymes
• moist heat causes coagulation of protein

• biocidal activity = high, intermediate, or low level
• the ability of the chemical disinfectant to destroy or inactivate organisms

• surface
• immersion disinfectants
• immersion sterilants
• hand antimicrobials

• inactivates spores in all forms (bacteria, fungus, viruses)
• used as a disinfectant or sterilant

• inactivates all forms of microorganisms BUT NOT viruses
• not a sterilant

• inactivates vegetative bacteria and certain lipid-type viruses
• do NOT destroy spores, tubercle bacilli, or nonlipid viruses

coagulation, precipitation, and oxidation of protein of microbial cells or denatures cell enzymes

• glutaraldehydes
• chlorine compounds
• iodophores
• complex phenolics

• high level disinfectant
• 2% neutral
• 2% alkaline
• 2% alkaline with phenolic buffer
• 2% acidic

• chlorine dioxide-main ingredient
• use life: 1 day
• economic, hassle, corrosive

• sodium hypochlorite- 5.25%
• oxidation of cell wall and enzymes
• uses water purification

• 1% iodine
• releases slowly to disinfect
• anti-microbial
• surface disinfectant
• mixed with distilled water
• for: environmental surfaces (countertops)

• protoplasmic poison destroys cell walls
• chemical disinfectant in lower concentrations
• surface disinfectant-o-phenylphenyl 9% with o-benzyl-p-chlorophenol 1%

• high level disinfectant
• not a surface disinfectant due to toxic fumes
• damage to nucleic acids and proteins
• limitations: 28 day cycle, caustic to skin, eyes, bad to inhale
• rinse very well in sterile water, can be corrosive and toxic

• are only used for items that cannot be sterilized by heat
• limited used due to no spore testing available
• can be contaminated over time
• inefficient: needs to stay in solution 24 hrs
• not recommended
• rinse with sterile water

• critical
• semi-critical
• non-critical
• environmental

• penetrates soft tissue or bone
• needle, currette, explorer, probe
• sterilize or dispose

• touch mucous membrane or oral fluids, does not penetrate
• radiographic biteblock, ultrasonic handpiece, amalgam condenser, mirror
• sterilize, high-level of disinfection when necessary

• does not touch mucous membranes, only contacts unbroken epithelium
• light handles, certain x-ray machine parts, safety eyewear
• cleaning and tuberculocidal, intermediate-level disinfection

• no contact with patient surfaces, or skin
• countertops, equipment surfaces, housekeeping surface
• cleaning and intermediate-low disinfection

the agent will not penetrate or remove the film of microorganisms

• agents used - iodophors, sodium hypochlorite, complex phenols
• procedure - spray disinfectant, scrub vigorously, use wet gauze, spray and leave surface wet
• unit water lines - biofilm can form in standing water lines. flush waterlines 2 minutes at the start of each day, run water through tubing 30 sec before and after pt.

decreases the risk of introducing septic material into the soft tissue from the needle of the mucosa penetrating into deeper tissues. the microorganisms on the surface can be carried into the tissue