Testing for thermodisinfector and autoclave - Aftercare and maintenance
Testing for thermodisinfector and autoclave
To check whether the device has done what it should do, it is not possible to rely on the information provided by the device itself.
Just as a car sometimes has a breakdown, but can still drive on, the process of cleaning, disinfection and sterilization could also have been performed incompletely due to a slight disturbance.
In order to evaluate the operation, it is therefore necessary to regularly test each device by means of objective test methods that accompany the device. Only with a good result of such a test there is certainty about sufficient results and the processed instruments are safe for use.
Testing for the thermodisinfector
Checking for the correct execution of the disinfection process is difficult to determine only on the eye. Of course, in the case of visible contamination of the 'clean' instruments, something is wrong with the thermodisinfector, but invisible contamination also indicates insufficient machine performance.
In order to gain insight into the functioning of the thermodisinfector, various manufacturers have developed tests that give an indication of the disinfecting effect of the thermodisinfector. There are no official guidelines for such tests yet. At this moment it is better to test than to test, even though the tests may need to be adjusted in the future.
A Tosi test for thermodisinfector. B Miele test kit for thermodisinfector
It is possible to manually keep a process documentation, but that is also possible by connecting a serial printer to a serial interface (SST) for printing the cleaning and disinfection process. With this interface, the process documentation can be done very simply and reliably via software.
Archiving of the printouts must be done in orders. A list of printer recommendations is also available at Miele.
Such tests could dictate a weekly check.
Testing for the autoclave
To check the sterility of solid instruments, use can be made of the so-called TST test strip (time-steam temperature). These strips only show the correct discolouration as in:
- A humid environment (steam);
- For at least 3 minutes (time);
- A temperature of 134 ° C (temperature) prevailed.
Or as with an alternative run:
- For 15 minutes;
- At 121 degrees.
A Test strip for sterilization of solid instruments. B Test strip for sterilization of solid instruments. C Helix test to test sterility of hollow instruments. D Results card for Bowie and Dick test to test the vacuum operation of the autoclave
The 'barcode' applied on sterilizable tape (and also on sterilization bags) does not guarantee that the sterilization has been carried out properly. The dashes are discolored by heat, but it is impossible to check how hot it has been and not at all how long it has been hot. A discoloration is therefore at most an indication of whether the instruments have already been in the autoclave or not.
To check whether sterility has been achieved in cavities, a TST strip is insufficient and a different type of test must be performed. The 'helix' test, adapted for use in dentistry and the standard Bowie and Dick test (see the special program on the autoclave) is available for this.
It is advisable to sterilize a 'helix' with each surgical instrument. You really know for sure that the run is sterile in every nook and cranny. The costs of the test make this application possible.
The standard Bowie and Dick test (steam penetration test) can be applied if there are hardly or no surgical procedures in practice. A weekly Bowie and Dick test seems sufficient.
Stick the receipts, readers or check strips on a date in a notebook. Should a source study be carried out into a patient's illness as a result of treatment in the dental practice, then it must be possible to demonstrate that the equipment has worked well. The burden of proof therefore lies in practice in such situations. A storage period of one year could be maintained for that, or as long as possible (a notebook does not take up much space and can last longer than a year).
Checking the ultrasonic cleaning device
Always leave the appliance empty, cleaned, disinfected and dry after a working day. The lifespan of ultrasonic cleaning devices is limited. That is why it is good to regularly check its operation:
- Fill the cleaning device with water and let it vibrate for ten minutes to remove the dissolved gas.
- Add a drop of detergent.
- Cut a few small squares of aluminum foil and add them.
- Turn on the ultrasonic cleaning device.
Spontaneous holes in the film must be formed within a few minutes. This is an indication that the ultrasonic cleaning device is still functioning properly. With the Sono Check test, the color changes from green to yellow with sufficient energy. Sono Check does not contaminate the ultrasonic cleaning device and can be used in the instrument load.
Sonocheck is a standardized test that does not contaminate the ultrasonic cleaning device