Thursday, August 3, 2017

The Life of a Dental Instrument - Sterilization

Here at Coastal Maine Pediatric Dentistry our sterilization process is quite detailed. We thought you should know more about sterilization aside from the fact that instruments go in dirty and come out clean. Let me walk you through step by step what our instruments go through for each and every patient.

We have two separate sterilizing units, an ultraclave and a statim.  Every morning we run a Biological indicator (BI) through our ultraclave, A Biological indicator (BI) is the highest standard for sterility assurance. BI’s contain bacterial spores that test the lethality of sterilizers. The principle behind this is, if your sterilizer can effectively kill the highly resistant spores in the BI. Then we are confident it is capable of killing the less resistant organisms that could find their way onto our instruments. We mail in our BI’s every Monday after they are run through our ultraclave. Per CDC guidelines they need to be run at least once a week. Another monitoring system that we use is chemical indicators that monitor all steam sterilization processes. The indicator will turn dark brown to show that the contents are sterile. A chemical indicator goes in every statim cycle, along with being put into every wrapped cassette that goes in the ultraclave. At the start of the day one is run through both the statim and ultraclave to be kept for day to day monitoring consistency.

Dirty instruments and cassettes come into sterilization and are rinsed off and put into our Biosonic. The Biosonic is an ultrasonic cleaning process created by high frequency soundwaves. The soundwaves create high energy cavitation, cavitation being the formation of an empty space within a solid object or body. During cavitation millions of tiny bubbles form and then explode, releasing enormous amounts of energy and shockwaves. This powerful action reaches into the tiniest of crevices which cannot be reached by manual scrubbing. The combination of energy and specially formulated solutions makes ultrasonic cleaning the most effective method for removing microscopic debris.

After the instruments are done in the Biosonic they are taken out and thoroughly rinsed off before being put in the dryer. It’s important to dry the instruments after cleaning them because it cuts down the chance for instrument corrosion during sterilizing.

Once the instruments have finished the drying cycle they are either packaged or wrapped. Cassettes that go in the ultraclave get wrapped in a special cassette wrap with a chemical indicator on the inside. Loose instruments get bagged in sterilization pouches to be put in the statim. Before the lid to the statim closes we put a chemical indicator inside.

The statim’s unique steam injection technology allows the unit to be fast, compact, and reliable. The steam injection system eliminates 98% of the air in the sterilization cassette which helps achieve as close to hospital level sterilization as possible in an office setting. When the start button is pressed on the statim, the steam generator heats to the optimum temperature and distilled water is pumped in and converted to steam. A wall of steam is injected in to the cassette pressure chamber which has been loaded with the instruments that have now come out of the ultrasonic and been dried. Air is purged as the steam goes through the cassette and is continuously flushed into a waste bottle. After any cycle is completed the drying cycle switches on, rapidly drying and cooling the instruments.

The other sterilizer is the Ultraclave. The Ultraclave sterilizes the wrapped cassettes. Once you close the Ultraclave sterilizing chamber, air is forced out by pumping in steam. High pressured steam quickly raises the internal temperature. On every Ultraclave there is a thermometer that is waiting for the thermal point of 268-273 degrees Fahrenheit. Once that temperature is reached it starts its sterilizing timer. During the sterilizing process steam is continuously entering the Ultraclave thoroughly killing all dangerous microorganisms. Once the required time of sterilization is completed, the chamber will exhaust the pressure and steam allowing the door to open for cooling and drying.

Once all the instruments are sterilized they are put on drying racks where they will be picked up by hygienists or assistants for use.

Nicole - Dental Assistant