All too often little consideration is given to sterilization or reprocessing areas in either existing or newly designed dental practices. Yet it is increasingly important to meet today's hygiene rules regarding reprocessing instruments between patients.

1. 106 Australasian Dental Practice January/February 2016
I
t is recognized all too often
that very little consideration
is given to sterilization or
reprocessing areas in either
existing or newly designed
dental practices. And yet
reprocessing instruments
between patients is crucial to
meet today’s hygiene rules in
dental practices.
Dental practitioner’s also have a moral
and legal duty of care calling for effective,
well-defined and implemented infection
control measures to prevent the trans-
mission of infectious diseases to patients
and staff.
Reprocessing areas
It is particularly noticeable that since the
emergence of SARS, the avian influ-
enza outbreaks and the recent 2015 Ebola
pandemic in Africa, that patients have
become more sensitive to hygiene issues,
not hesitating to question dental profes-
sionals about asepsis rules and standard
precautions. This is also the case with
tattoo, piercing and podiatry salons.
In Australia, a breakdown in infection
control protocols in a number of Sydney-
based dental surgeries in early 2015 raised
fears of possible exposure of patients
to blood-borne viruses. This and other
similar incidents have focussed the atten-
tion of the Dental Board of Australia on
infection control standards.
Beyond the purely regulatory and safety
aspects, many dentists have made the ster-
ilization area of their practice a key asset
for their activity. Locating this in a prime
and visible location lets patients see up
front that their health and safety is impor-
tant. The staff don’t hesitate to share this
passion for hygiene with patients, happy
to answer any questions they may have.
Flattered by this attention, it makes the
patient feel confident and secure.
Fundamental principles
in designing reprocessing areas
By Christian Stempf
infection | CONTROL
Figure 1. Instruments must travel in one direction in the reprocessing (i.e. sterilisation) area from the dirty zone towards the clean
zone. Conversely, airflow should be designed to prevent air from the dirty zone being forced into the clean zone.

2. 108 Australasian Dental Practice January/February 2016
infection | CONTROL
Disposal Soaking Rinsing Cleaning Rinsing
Basin
1
Sonic
cleaner
Sharp
Garbage
Basin
2 Demin. water
supply
Handwashing
Sink
Figure 2. Dirty instruments are cleaned and rinsed on entry to the reprocessing area.
To create new reprocessing areas or
enhance existing ones is not an “insur-
mountable” challenge. It simply requires
some basic principles that this article
will outline.
The amount of space required
Having sufficient space dedicated to
the reprocessing area is essential. In
many cases, it is undersized. The room
must be functional, well lit and in propor-
tion to the size of the dental practice and
volume of instruments to be reprocessed.
There must be space for cleaning and
sterilization devices with their respec-
tive accessories, as well as enough bench
space for intermediate stages i.e. instru-
ments before/after cleaning; before/after
packaging; and after sterilization.
The first fundamental principal is to
have two zones: a dirty zone and a clean
zone. Rationally, instruments must travel
in one direction from the dirty zone
towards the clean zone. As a consequence
of this one-way flow, processed (clean)
instruments must not enter the dirty zone;
hence one preferred design for a repro-
cessing area would be rectangular - a
corridor with two doors (IN and OUT)
(Figure 1).
Both zones require ventilation and the
airflow should be designed to prevent air
from the dirty zone being forced into the
clean zone. Where the areas are beside
one another, this can be achieved by
pressurizing the clean area though air con-
ditioning outlets and/or having exhaust
fans in the dirty area.
At the entrance, there should be a hand-
washing basin. Having a wall-mounted
liquid soap dispenser means this can be
operated by the elbow, which avoids con-
taminating it with soiled hands.
Form follows function
The configuration of each part of the
sterilizing room follows the repro-
cessing steps i.e. cleaning and rinsing;
packaging; and sterilization. This room
must not be used for any other purpose.
Floors and working surfaces must be
smooth and edges and be easy to clean.
Soaking
In order to prevent blood, saliva and
debris from drying, if not cleaned imme-
diately, it is prudent to place instruments
into a holding solution containing deter-
gent. Note the manufacturer’s guidelines
NOT to immerse or soak certain items such
as handpieces in solutions, which instead
require specific lubrication. Having the
holding solution warm will make this step
more effective. The temperature of the
solution should not exceed 40-45°C, thus
preventing coagulation of blood proteins.
After soaking, the instruments should be
rinsed free of the holding solution and
then cleaned using mechanical cleaning
(e.g. ultrasonic baths or instrument washer
disinfectors for solid instruments).
Cleaning
The cleaning step is of utmost impor-
tance. Manual cleaning is discouraged,
as this is the least efficient method of
cleaning particularly for complex or
hollow instruments and rough surfaces.
It also poses more health and safety con-
cerns because of the risk to staff of skin
penetrating injuries.
After ultrasonic cleaning, thorough
rinsing is essential to remove chemicals
and bioburden. This is normally done with
tap water. Ideally this would be followed
by a second rinse with demineralized
water to eliminate residues and salts pre-
sent in tap water that could lead to stains
on sterilized instruments (Figure 2).

3. January/February 2016 Australasian Dental Practice 109
infection | CONTROL
Disposal Soaking Rinsing Cleaning Rinsing Drying - HPs Packaging Sterilization
Basin
1
Sonic
cleaner
Area for
drying / high-
low-speed
maintenance
Area for
storage
prior to
sterilization
Sharp
Area for
cooling and
labelling
Garbage
Basin
2
Handwashing
Sink
Compressed
air supply
Figure 3. Clean and dry instruments are then packaged and sterilised.
Instrument washers (also known as
thermal disinfectors or washer-disinfec-
tors) are a preferred mechanical cleaning
method, since they give a clean, dry
and disinfected load at the end of the
cycle. Their cleaning cycle includes pre-
washing, rinsing, washing and drying
without manual intervention.
Bench space for
inspection and sorting
Next to the sink, space is needed
to check the dryness, cleanliness
and integrity of items which have been
through the cleaning processes. There also
needs to be provision for handpiece lubri-
cation systems, which range from pressure
pack units through to dosed lubricators to
handpiece combination lubricators and
sterilizers. Using pressure pack lubrica-
tion cans does not give complete internal
cleaning of handpieces.
Packaging
In this area will be pouch heat sealing
devices as well as space for packages to
be labelled with batch numbers until they
are to be sterilized. To ensure safe and
efficient sterilization, it is crucial to check
the correct cycle is being used for the type
of load (e.g. wrapped cycle for wrapped
items) and that the parameters have been
validated for the type of load.
Sterilizing
Additional space beside the sterilizer is
needed for items to cool and for the
record books which keep details of each
cycle as well as for storage of printouts.
Special attention must be paid to ensure
that pouches are hermetically sealed and
are completely dry. Damp packages are
not acceptable as sterile (Figure 3).
Once cool, packaged items can then be
transferred to storage. This is normally
outside the reprocessing area and in the
surgery (operatory) in drawers or cabi-
nets that are kept closed so the items are
no exposed to dust, aerosols or splashes
of material.
Conclusion
All readers should reflect on these
definitions:
• Reprocessing: “All activities that are
required to ensure that a used medical
device is safe for reuse”.
• Sterilization: “A validated process
used to render a product free from
viable microorganisms”.
• Duty of care: “The individual prac-
titioner is responsible for ensuring
compliance with infection control
requirements throughout the prac-
tice. This cannot be delegated.” (ADA
Guidelines, Third Edition 2015)”
Always bear in mind that each step of
the reprocessing cycle is important. None
shall be rushed or skipped, which would
compromise sterility and the safety of
patients and staff.
About the author
Christian Stempf has worked exten-
sively within the European dental
industry. He has been involved in infec-
tion prevention for over 20 years with a
focus on reprocessing reusable medical
devices, in particular sterilization and
organization of sterilization areas. He
is a member of the European (CEN-
TC102) normalization committee
participating to two working groups i.e.
benchtopsterilizers(EN13060)andwasher
disinfectors (EN15883).