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 in the following article:

1. CATEGORY
F E AT U R E : I N F E C T I O N C O N T R O L
Real risk from
infection control breakdowns
T
he 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 nonsterile 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 best
Infection 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
98 AUSTRALASIAN DENTIST
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 essential
However, 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.

2. F E AT U R E : I N F E C T I O N C O N T R O L
CATEGORY
Infection control built
into A-dec dental units
T
he 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.
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-tomeasure 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.
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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 bottle
A-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 Treatment
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.
Waterline 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 WH 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.
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CONTACT: Shal Hafiz A-dec Australia 1800 225 010
www.a-dec.com.au
More information: A-dec 1800 225 010
www.a-dec.com.au
AUSTRALASIAN DENTIST 99