Instrument processing is an essential element of the infection control program for dental hygiene procedures. Although it may not be a primary task for the hygienist each day, every hygienist is dependent on the procedure in order to have sterile instruments for patients. Proper processing of dental instruments is accomplished through cleaning, drying, packaging, sterilization and storage.
Because most hygiene instruments have blood on them after treatment, cleaning is extremely important to assure that all debris is removed so the instruments can be properly sterilized. In the past, many dental assistants and hygienists hand scrubbed instruments, which resulted in injuries due to spatter of contaminants or punctures to the hands. Using ultrasonic instrument cleaners or instrument washers is a safe and more efficient method for cleaning instruments. However, I often hear complaints from team members who say that the ultrasonic cleaner doesn’t get the instruments clean, so they feel compelled to scrub them. In that case, I suggest some trouble-shooting procedures.
First, remember that if instruments sit in the instrument processing area for a long time, the debris dries and makes them harder to clean. The best practice is to put instruments immediately into the ultrasonic unit or a holding container with ultrasonic solution to prevent drying. There are several new products that are enzymatic pre-cleaners that can be applied to the instruments prior to placement in the ultrasonic unit or instrument washer.
If an ultrasonic unit is used to clean instruments, be sure to cover the unit when it is running and allow for a long enough cycle of cleaning. Always consult the manufacturer’s directions for your ultrasonic unit, which recommend times dependent on the size of the unit and other factors, such as whether the instruments are loose or in containers.
Ultrasonic units can be checked periodically for effectiveness by suspending strips of aluminum foil into the unit filled with water or cleaning solution. The foil should be as wide and deep as the unit, and the strips should be spaced throughout the tank. Run the unit for one to two minutes. If the unit is functioning properly, when the foil strips are removed there should be an even distribution of perforations or pinholes on all the foil strips.
Enzymatic cleaning solutions tend to be more effective than general-purpose cleaners for removing blood. These cleaners come in liquids, powders, and tablets. Some of these solutions can also be used for cleaning suction lines, but consult the manufacturer’s directions first. Only specially formulated ultrasonic cleaning solutions should be used in the units to prevent damage or corrosion to the tank.
Once the instruments have been thoroughly cleaned, they should be rinsed and inspected to make certain that all debris has been removed. An instrument washer eliminates the need to rinse, and some models also have a drying cycle. Excess moisture should be removed from instruments prior to sterilization by allowing the instruments to air-dry, or by using a commercially available instrument dryer. Moisture can interfere with the sterilization cycle, cause rust or corrosion on the instruments, or tear packaging materials.
The CDC Guidelines for Infection Control in Dental Health Care Settings recommend that instruments be packaged if they are not used immediately after being removed from the sterilizer. Packaging instruments protects them from potential contamination during storage. The packaging material must be appropriate for the type of sterilizer used. Many offices use self-sealing pouches, which are available in many sizes and determined by the number and size of items to be sterilized.
Packaging individual instruments or ultrasonic inserts that are extra items in instrument sets is particularly important. If these items are stored in treatment rooms unpackaged, it is likely they could become contaminated when touched by contaminated hands or aerosols.
Always follow the manufacturer’s instructions for loading items in the sterilizer, and pay attention to the maximum number of items or packages that the sterilizer can accommodate. Overloading is a common cause of sterilizer failure.
Once the sterilization process is complete, leave the instrument packs in the sterilizer until the drying cycle is complete. Handling wet instrument packages can cause packaging material to break or tear, compromising the sterility of the instruments. If the instrument packs are still wet after the drying cycle is complete, the sterilizer may have been overloaded or the unit may be malfunctioning.
Sterile instruments should be stored in closed containers or cabinets to protect them from damage and potential contamination.
I call instrument processing a necessary evil. It is a task that we struggle to find time for, but absolutely cannot function without.
Mary Govoni, CDA, RDH, MBA, is the owner of Clinical Dynamics, a consulting company based in Michigan. She is a member of the Organization for Safety and Asepsis Procedures and is a featured speaker on the ADA Seminar Series. She also writes a column for Dental Equipment & Materials magazine. She can be contacted at [email protected].
