98 AUSTRALASIAN DENTIST

CATEGORY

Real risk frominfection control breakdowns

temperature plateaus (at 180°C) required by dry heat sterilizers. The lower temperatures possible in steam sterilization does not damage instruments like dental hand-pieces.

Vacuum cycle essentialHowever, the heat from steam is only effective if it reaches all parts of the instruments, including inside turbines where biofilm may accumulate. This means that a pre-vacuum cycle is essential to remove all trapped air from within high and low speed instruments or porous products. The Lisa Fully Automatic is the only bench-top sterilizer currently with an air detector (that also enables weekly rather than daily vacuum testing).

The Australian/New Zealand standard AS/NZ 4815:2006. states: “The choice of sterilizer and selected sterilization cycles may be inappropriate for particular items or types of loads.”

This is an important point to note, as some sterilizers sold in Australian only feature S & N sterilization cycles, which may NOT be suitable for common instruments, like turbines and handpieces or even simple ‘box’ joints found in scissors or tweezers which may trap air.

The threat to patients and clinical staff from failing to adhere to effective infection control measures is very real, with

the WHO reporting that worldwide 2 million patients contract Healthcare Associated Infections (HCAI) each year. This includes up to 100,000 healthcare-related infection deaths!

Not surprisingly, the importance of reprocessing dental instruments using a bench-top sterilizer or ‘autoclave’ has been industry practice for some time, notably even more so following the HIV pandemic first identified in the 1980’s.

While vacuum-steam sterilizers offer by far the best infection control solution in dental surgeries, there remains some confusion on the various sterilization ‘cycle types’ described under the European Norms (applying to sterilizers also used in Australia). There are three main cycle types, B, S & N. A description of each is given below:

Cycle types

N Cycle:

Appropriate exclusively for unwrapped (Naked) solid products. WARNINGS: No transportation, no storage, for immediate use only.

S Cycle:

Designed for processing Specific products as specified by the manufacturer. WARNINGS: This cycle is used only for the specific loads it was designed for to avoid risk of cross infection from non-sterile items.

B Cycle:

Provides medical grade sterilization equivalent to a Big (i.e. hospital) sterilizer. Type B cycles are suitable for all load types.

Of course, sterilization is just part of an effective infection control protocol, which should include an established and repeatable workflow process including pre-cleaning, soaking, bagging, sterilization, proper storage and critical instrument tracking. It also extends to use of gloves, gowns and bibs, cleaning of all equipment and bench surfaces in the surgery, plus control of airborne aerosols and treatment of dental unit waterlines.

It is important that infection control processes be understood and documented, and that they be followed each time by sterilization room staff, so that no steps are left out.

Steam sterilizers bestInfection control experts agree that heat in the form of saturated steam is the most effective method of sterilization, and that today’s bench-top sterilizers with ‘B-type’ cycles match the effectiveness of hospital grade units.

However, sterilization of dental instruments is only effective if the sterilization cycle is appropriate for the type of instruments being processed and that the sterilizer is regularly tested and validated. Recording of sterilization data is also recommended to allow tracking of critical instruments to successful sterilization cycles.

A-dec Australia’s W&H product manager, Shal Hafiz, said steam releases 300 times more energy than dry sterilization, reducing cycle times by two thirds and enabling lower temperatures to be used (134°C), compared to the much longer times and longer high

F E AT U R E : I N F E C T I O N C O N T R O L

AUSTRALASIAN DENTIST 99

CATEGORY

Infection control built into A-dec dental unitsThe innovative A-dec design eliminates trapped, stagnant water.

That mean clean water circulates every time you activate a handpiece.

Whenever water is used in dental handpieces there is a need to ensure a clean water supply to prevent the potential of airborne aerosols spreading infection.

That’s why A-dec has designed its dental units together with a complete and easy-to-use system of dental unit waterline maintenance to ensure dental staff and patients are protected – without exception.

Simply put, A-dec’s approach to dental equipment design in all A-dec 200, A-dec 300, A-dec 400 and A-dec 500 dental units keeps clean water in and contaminants out.

The A-dec Control Block.This begins with the heart of the A-dec dental unit, its unique patented A-dec design solid brass-core control block that has been engineered with patient health in mind.

The innovative A-dec design eliminates trapped, stagnant water. That means clean water circulates every time you activate a hand-piece.

The A-dec water bottle eliminates opportunity for contamination.

A-dec water bottleA-dec recommends that the dental team should never expose clean water to ambient contaminants or sink splatter. With A-dec’s internal pickup tube design, the A-dec water bottle eliminates opportunity for contamination.

The A-dec water bottle also includes a sure-fit connection, making refilling easy.

And its heavy-duty construction maintains its shape and holds up under fluctuations in pressure.

A-dec makes its own tubing from virgin polyurethane, which is blended with Antimicrobial Alphasan® to provide added protection from microbial contaminants.

ICX® Waterline TreatmentWaterline maintenance protocols should be convenient and easy to use. Not all systems are, which is why A-dec developed its easy to use ICX waterline treatment tablets.

The patented A-dec ICX formula keeps your waterlines clean and odour-free. Adding an effervescing tablet with each refill of the water bottle makes maintenance simple. No other product is as easy and effective, protecting your team, your equipment and your patients.

And of course, A-dec’s streamlined aesthetic dental unit design includes easy to clean surfaces, together with thermo-washer safe and sterilizable W&H hand-pieces supporting the highest standards of infection control in the surgery.

For a short video explaining A-dec’s waterline maintenance system visit the A-dec website to download a free copy of the A-dec asepsis guide. u

More information: A-dec 1800 225 010 www.a-dec.com.au

These instruments usually require ‘B’ type cycles, which W&H recommends as a default setting to removes the risk of selecting the wrong cycle type, which could result in a breakdown of infection control and unnecessary infection risk.

Drying important!A-dec’s W&H product manager, Shal Hafiz, cautioned about using very short cycle times with large loads, as this may affect the penetration of steam and said it was also important to allow sufficient drying time. He urged users not to rely solely on manufacturer’s claims without doing proper validation testing or checking that pouches are fully dry at the end of the cycle (i.e. all instruments and pouches should be dry prior to opening the door of the sterilizer).

“Wet pouches are permeable which allows microorganism to penetrate and multiply”

This is because wet pouches are permeable which allows microorganism to penetrate and multiply. Moisture left inside turbines that have been sterilized without an effective drying cycle may cause corrosion and will significantly reduce their lifespan.

Taking these factors into account, Mr Hafiz recommended the latest Lisa Fully Automatic sterilizer with its made-to-measure automatic cycles as the best investment in effective infection control.

Instrument tracking The Lisa has inbuilt data logging, can be linked to patient management software and also connected to an automated Lisasafe bar code printer for labeling sterilized pouches. These labels can be easily scanned at the point of use for full instrument tracking without the risk of the transcriptions errors that can occur with manual logs.

When used with the Lisa 500 or Lisa Fully Automatic sterilizer, the W&H Lisasafe has an added inbuilt safeguard, which prevents it producing pouch labels if a cycle has failed, or the operator has not released the load for some reason (such as moist packaging, failed chemical strips, etc). The Lisa also has self-test function and full on-board data logging. u

More information on Lisa sterilizers is available from A-dec Australia, including sterilization instruction sheets with infection control protocols for the steri room and useful information on effective dental unit waterline maintenance.

CONTACT: Shal Hafiz A-dec Australia 1800 225 010 www.a-dec.com.au

F E AT U R E : I N F E C T I O N C O N T R O L