Infection Control Ch. 21

direct contact for the correct time is insufficient between the sterilizing agent (chemical or steam) and all surfaces of the items being processed

A load may fail to become sterilized when?

dry the instrument thoroughly

An alternative to rust inhibitors is to

steam under pressure

An autoclave is used to sterilize dental instruments and other items by means of

soft tissue or bone

Critical instruments are items used to penetrate what?

physical, chemical, and biologic.

Currently, three forms of sterilization monitoring are used:

Heat-up cycle Sterilizing cycle Depressurization cycle Drying cycle

Dental office steam sterilizers usually operate through four cycles:

320-375 degrees F

Dry heat sterilizers operate at approximately

forceps, scalpels, bone chisels, scalers, and burs

Examples of critical instruments include?

(PID) of the x-ray unit , lead apron, or the curing light that comes into contact only with intact skin.

Examples of noncritical instruments?

12 min

Exposure time in forced air sterilizers, after the sterilizing temperature has been reached, ranges how long for packaged items?

6 minutes

Exposure time in forced air sterilizers, after the sterilizing temperature has been reached, ranges how long for unpackaged items?

1-2 hrs

Heat is transferred from the static (nonmoving) air to the instruments in about

through contact with contaminated instruments or other patient-care items

How can the dental assistant can be exposed to microorganisms?

By looking at the gauges and readings on the sterilizer and recording the temperatures, pressure, and exposure time.

How is physical monitoring of sterilization done?

10 hrs

How long should items stay in the glutaraldehyde sterilization?

steam sterilization.

Instruments and burs made of carbon steel will rust during

Hand scrubbing Ultrasonic cleaning Instrument washing machines.

Instruments may be precleaned in one of three ways:

percutaneous injury

Most common way a dental assistant can get a bbp is through?

the chemicals' toxicity.

OSHA requires a material safety data sheet (MSDS) on the chemical vapor solution because of?

they may burn or discolor from the intense heat.

Paper and cloth packs should be avoided because

20 psi

Pressure factor in chemical vapor sterilization should measure?

packages that were processed and those that were not processed.

Process indicators are useful in distinguishing between what?

a certain temperature

Process indicators simply identify instrument packs that have been exposed to

multi-parameter indicators

Process integrators are also known as?

indicate sterility and are not a replacement for biologic monitoring.

Process integrators do not do what?

sodium nitrate

Rust inhibitors such as

film pouches or paper bags, nylon see-through tubing, sterilization wrap, and wrapped cassettes.

Standard packaging for chemical vapor sterilization includes ?

all microbial forms, including bacterial spores

Sterilization destroys what?

270 degrees F (131 C)

Temperature factor in chemical vapor sterilization should measure?

instruments will not rust if they are thoroughly dry before they are placed in the sterilizer.

The advantage of dry heat is

endodontic files, orthodontic pliers, wires, bands, and burs.

The low water content of the vapor prevents destruction of items such as

it does not rust, dull, or corrode dry metal instruments.

The major advantage of the chemical vapor sterilizer is that

steam sterilization chemical vapor sterilization dry heat sterilization

The three most common forms of heat sterilization in the dental office are :

Process indicators Process integrators

The two types of chemical indicators are:

static air and forced air.

The two types of dry heat sterilizers available are

heat-resistant

The wrapping material must be

20-40 min

Time factor in chemical vapor sterilization should measure?

the heat

What actually kills the microorganisms?

improper instrument cleaning or packaging and sterilizer malfunction

What are some factors the can cause the sterilization process to fail?

minimize corrosion and pitting.

What can distilled water do?

combination of pressure, temperature, and time.

What do process integrators respond to?

dry heat and chemical vapor

What does not rust carbon steel instruments?

moisture may cause corrosion on some high-carbon steel instruments

What is a disadvantage of steam sterilization?

Rapid or "flash" sterilization of dental instruments

What is accomplished by rapid heat transfer, steam, and unsaturated chemical vapor?

Glutaraldehyde

What is not recommended for a holding solution?

flushing the handpick

What is the best way to remove debris from the head of the handpiece?

hand scrubbing

What is the least desirable method of cleaning instruments?

Biologic monitoring, or spore testing

What is the only way to determine if sterilization has occurred and all bacteria and endospores have been killed?

2.0-3.4% glutaraldehyde

What liquid sterilization should be used for rubber dam frames, shade guides, and x-ray film holding devices?

Flash sterilization

What may be used only on instruments that are placed in the chamber unwrapped?

CDC, ADA, and OSAP

What recommends at least weekly biologic monitoring of sterilization equipment?

EPA-registered intermediate-level or low-level disinfectant after each patient use.

What should noncritical instruments be cleaned and processed with?

steam and chemical vapor sterilizers

What type of sterilization should be used when sterilizing the handpiece?

Distilled water

What type of water should be used in autoclaves?

only when instruments are needed immediately (non critical and semi-critical)

When is flash sterilization used?

Forced air sterilizers

also called rapid heat transfer sterilizers, circulate the hot air throughout the chamber at a high velocity.

Process indicators

are placed outside the instrument packages before sterilization.

Ultrasonic cleaners

are used to loosen and remove debris from instruments.

HVE tips, Rubber dam forceps, Amalgam carriers

examples of semi critical instruments?

17-20 min.

how long should cassettes be cleaned in the ultrasonic?

once a day

how often should ultrasonic solution be changed?

Ethylene oxide

ineffective on wet items. Toxicity is a risk if the gas is not handled properly.

Semicritical items .

instruments touch mucous membranes or nonintact skin and have a lower risk of transmission.

Steam sterilization

involves heating water to generate steam, producing a moist heat that rapidly kills microorganisms.

Chemical monitoring

involves the use of heat-sensitive chemical that changes color when exposed to certain conditions.

Dry heat sterilizers

operate by heating up air and transferring that heat from the air to the instruments.

circulation of sterilizing agent.

packaged materials that are placed in the sterilization must be placed in single layers to allow what?

Process integrators

placed inside instrument packages

Noncritical instruments

pose the least risk of transmission of infection because they contact only intact skin, which is an effective barrier to microorganisms.

Transport Cleaning Packaging Sterilization Storage Delivery Quality

steps for instrument processing

Chemical vapor sterilization

very similar to autoclaving, except a combination of chemicals (alcohol, formaldehyde, ketone, acetone, and water) is used instead of water to create a vapor for sterilizing .

because residual chemical vapors containing formaldehyde and methyl alcohol can be released when the chamber door is opened and can be irritating to the eyes

what are the disadvantages chemical vapor sterilization?