THE STERILIZATION PROCESS

The sterilization process takes place in a CSR. There are many benefits to the centralized approach. Centralized instrument decontamination and sterilization are usually safer and more cost effective than instrument processing in the DTR. The

Figure 10-2.\Operating a dental handpiece in CSR.

Figure 10-3.\Contaminated instrument pack placed at the entrance of the receiving area in the CSR.

ULTRASONIC CLEANING.\This process is safer and more effective than manual scrubbing. The ultrasonic cleaner eliminates the possibility of accidental puncture wounds on the hands that frequently occur with manual scrubbing. It also eliminates the splatter of organism-laden debris generated by scrubbing with a brush. The ultrasonic cleaner uses electrical energy to generate sound waves. When the sound waves travel through the liquid, millions of tiny bubbles form and burst continuously. This process is called a "cavitation" effect. The bursting bubbles scrub everywhere the liquid can penetrate. Intricate surfaces and difficult access areas, such as burs, endodontic files, serrated instrument handles, and hinged instruments, are cleaned more thoroughly and rapidly. The usage life of cutting instruments, such as burs and endodontic files, is extended by thoroughly removing debris that interferes with the cutting surfaces.

There are several sizes of ultrasonic cleaning units. Figure 10-4 illustrates small and large size ultrasonic cleaners. The ultrasonic cleaner should be located in the processing area of the CSR. The manufacturer's instructions must be followed when using ultrasonic cleaners. These instructions should be posted or readily available in locations where the units are used.

The following general guidelines are common to the proper use of all ultrasonic cleaners:

Always keep the ultrasonic cleaner reservoir 1/2 to 3/4's full with ultrasonic solution at all times.

The solution must completely cover the items for the ultrasonic action to occur.

Avoid the use of disinfectants, plain water, and nonultrasonic soaps or detergents.

Cleaning solutions must be changed at least daily or sooner, if visibly contaminated.

When using the ultrasonic cleaner follow these guidelines

Place instruments into a perforated or wire mesh basket and rinse under water first.

Place basket holding the instruments into the ultrasonic cleaner unit filled with solution.

Never place items directly on the bottom of tanks. This would reduce the amount of ultrasonic waves produced and could damage the unit.

Always close the lid or cover on the unit when in use to decrease aerosols and avoid splattering of the solution onto adjacent surfaces.

Limit ultrasonic cleaning time to 5 minutes to avoid damage to instruments. Follow manufacturer's instructions for exact cleaning times for different models.

Longer cleaning times may be required for some nonmetallic instrument cassettes.

Never use your hand to remove instruments from the unit. Instead, use the basket to lift the instruments from the solution, drain, and rinse them under running water. Be sure to rinse the instruments thoroughly to remove all the remaining solution. Inspect the instruments for remaining blood or debris, then dry thoroughly.

MANUAL SCRUBBING.\Although manual scrubbing is time consuming and presents an increased potential for contamination injury, this method is effective for cleaning instruments when automated washer processors or ultrasonic cleaning units are not available. Triple-sink modules allow personnel to perform in an orderly sequence multiple functions such as prerinsing, soaking, washing, and final rinsing. While wearing heavy-duty utility gloves, face mask, plastic apron, and eye protection, place instruments in

Figure 10-4.\Small and large size ultrasonic cleaners.

a disinfecting solution, allow them to soak, and then scrub them under water to avoid generating splatter.