The role of proper instrument logistics.


Fewer instruments – better control

The type of equipment and the type of procedures in use at the clinic will to a very high extent determine the safety margin of decontamination. A very important issue, that is often foreseen, is the logistics of instruments. A common problem in many dental offices is an overload of instruments, which will contribute to a more difficult and time demanding procedure to keep track of all instruments and to make sure that storage and sterile as well as packaging/wrapping conditions are maintained.

An item heavily loaded with microbiological material will be more difficult to sterilize than one lightly contaminated (fig. 1). The most effective stage of any decontamination procedure is thorough cleaning and this should accompany or precede all disinfection procedures. The effect of cleaning, desinfection and sterilization is affected by the design of the cassettes/trays being used. Shadow effects may easily ensure from the use of solid cassettes so that instruments are not being properly cleaned, neither in washer disinfectors nor in ultrasonic bath.

Picture 1:
Endofile, sterilized but not properly cleaned and decontaminated before the sterilization process. In this case sterilization will fale.


Fastened but free

Instruments should be free and fastened on trays so that ultrasonic waves, water jets and steam can reach every part to clean and inactivate efficiently during the whole procedure of desinfection and sterilization. Even if fastened the instruments must be free and have no contact points/areas with the locking device. An area of contact will not be properly cleaned and disinfected (fig.2).

Picture 2:
In the case of ultrasonic cleaning instruments are best cleaned if instruments are fastened but free and have no contact with locking device.


Two different metals will cause corrosion

Corrosion is a common problem. When in the same fluid, instruments and other articles made of different metals may corrode, and corrosion destroys sharp and delicate instruments. Corrosion pits will also make the surface rough, which increases the possibilities of microorganisms to attach themselves to the instruments. Mixing different types of metal in a liquid solution will result in an electrochemical cell and cause corrosion – this is often the case during cleaning, ultrasonic bath and washer disinfectors when using aluminium trays and instruments in stainless steel or when cleaning carbon burs and burs made of stainless steel in the same liquid container (fig.3).

Picture 3:
Corrosion is a common problem when mixing different materials in the same fluid


Don’t make it too heavy

Metallic weight is another decisive in decontamination and sterilization. The heat energy from the ultrasonic waves in the ultrasonic bath and/or the water in a dishwasher or washer disinfector as well as the saturated steam from the sterilizer shall be concentrated on the instruments that are to be processed. A load that is too heavy lessens the effect of desinfection and sterilization.

The most efficient trays, from disinfection and sterilization standpoint will be trays/cassettes made out of a non-heat absorbing, non-heavy and non corrosion causing material (fig 4).

Picture 4:

Efficient trays should be made out of non-heat absorbing, non-heavy and non-corrosion causing material.


Tray-prep increases efficiency and security

A tray system should facilitate the handling of instruments through the whole hygienic circle. Evaluations of effective tray-systems have shown reduced time for handling the instruments at disinfection and sterilization.

To obtain a flow of instruments as secure and efficient as possible, the use of a system as complete as possible is recommended. Tray systems facilitate the flow of instruments and goods the whole way between treatment, via sterile area, to storing (fig 5). With a carefully planned tray system you can handle the tray, the accessories and the instruments (products) as one unit throughout the whole process of work. Secure handling of instruments also leads to minimizing prick- and puncture wounds.

Picture 5:
Tray systems should facilitate the handling of instruments through the whole hygienic circle.


Reduce the number of articles and save time and money

The time in need for handling sterile goods can be reduced, usually to half the time.Good control of and minimizing the number of instruments and materials result in less costs and gives the conditions of safer handling, decontamination and disinfection (fig 6). A good way to enhance the quality of the dental surgery.

Picture 6:
Evaluation of the handling of instruments with effective tray systems has shown substantially reduced time.


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