Cleaning and Infection Control of the Digitest II
• DO NOT AUTOCLAVE THE DIGITEST II POWER
UNIT, AS THIS WILL CAUSE DAMAGE TO IT.
• Ideally, the Power Unit should be protected using
appropriately-sized disposable plastic barrier
sleeves. Since the Digitest II incorporates sophis-
ticated electronic circuitry, it should not be directly
sprayed with or soaked in disinfectant. The device
may be disinfected by wiping it with a damp cloth or
paper towel sprayed with an EPA-approved high-
level surface disinfectant, and dried with a paper
towel. Follow the surface disinfecting protocol
specified by the disinfectant manufacturer.
• Autoclaving does not remove accumulated
debris. Before autoclaving, scrub the autoclavable
components with a brush, or clean in an ultrasonic
cleaner, using warm, soapy water.
• The Tooth Probes, Lip Clip and Wire Assembly may
be sterilized in any conventional steam autoclave
(132-135C for 15 min for gravity displacement or
4 minutes for prevacuum cycle, or using the manu-
facturer’s recommended procedure, if different).
Minimum cool down interval is 15 min.
Service and Maintenance
• Do not open the Power Unit, except to change the
battery. There are no user-serviceable parts inside.
Internal repairs are to be made only by authorized
Parkell personnel, by returning the unit to the
service address at the end of these instructions.
• Avoid dropping the Power Unit or subjecting it to
physical shock.
• Battery should be removed if unit is to be stored
unused for more than 30 days.
• To prolong battery life, the device automatically
turns off after 14 seconds of inactivity.
• When the battery capacity is low, the Left and
Right digital display digits will flash alternatively
while the unit is activated. Replace the battery as
explained in the section “Changing the Battery”.
• If a Tooth Probe becomes loose in the mount of
the Power Unit, it may be tightened by carefully
inserting a flat screwdriver blade into the split
metal base of the probe and gently expanding
the sides apart with a twist of the tool.
• Discard and replace any Tooth Probe if the
metal or the insulation becomes damaged
during use.
Changing the Battery (Figure 2)
• The Digitest II Pulp Vitality Tester comes with a
high-output, 9 Volt alkaline battery factory installed.
• The replacement battery may be a Radio Shack
23-553, Duracell MN1604, Panasonic 6AM6
or equivalent. Although rechargeable 9 Volt
batteries may be utilized, they will require more
frequent changing and charging because of the
considerable voltage required to perform the pulp
testing procedure.
• To replace a weak battery, remove screw (A) and
carefully lift off the plastic battery door (B) by gently
pulling it away from the Power Unit. Withdraw the
weak battery from the battery enclosure, and
unsnap the wire battery connector. Discard
battery in accordance with all applicable
environmental laws.
• The fresh battery should be snapped onto the
connector and placed in the Power Unit so the
top end attached to the connector is placed first
into the opening. Slight pressure on the bottom of
the battery will help it to slide home. Replace the
plastic battery door (B) by engaging the tabs on the
bottom first, and tighten the screw (A) gently.
Digitest II Setup, Prior to Performing
Pulp Vitality Testing
• Standard infection control
protocol should be followed
during pulp testing, by wearing
disposable rubber, vinyl or
nitrile gloves. When wearing
gloves, the circuit
is completed by
using the autoclav-
able Lip Clip and
Wire Assembly.
Plug one end of the
wire assembly onto
the socket on the
bottom of the Power Unit (C), and insert the Lip Clip
(D) into the other socket. Place a small amount of
toothpaste on the lip to enhance electrical conduc-
tivity, and then place the Lip Clip over the patient’s
toothpaste-coated lip, making good contact with
the mucosa.
• Although it is strongly recommended that gloves be
worn when performing vitality testing to maintain
accepted standards of infection control, if gloves
are not being worn, the ground wire need not be
used. The operator may complete the circuit by
making contact with the metal plate of the unit
and touching the patient’s cheek or chin with the
free hand.
• Remember that to accurately diagnose the condi-
tion of the tooth, pulp testing must be performed
on a patient who has not been anesthetized or
received gas analgesia. Make sure to use the
Digitest II tester BEFORE you administer local
anaesthesia or gas analgesia.
• The tooth to be tested and the adjacent teeth must
be clean and dry. Interproximal embrasures should
be made free of any impacted food debris, saliva,
water or plaque by flossing or scaling with an
instrument and air-drying before testing.
• It is often useful to electrically isolate the tooth
being tested from neighboring teeth or metallic
restorations by wrapping it with a clear mylar
strip, such as those used in fabricating Class III
composite restorations.
• A dry cotton roll should be placed in the
buccal vestibule to isolate the tooth from the lip
and cheek.
• A plastic mirror should be used to keep the tongue
off of the tooth during testing.
• Insert Tooth Probe (E) into
the open end of the Power
Unit. To enhance electrical
conductivity and contact
between tooth and probe,
apply a small amount of
toothpaste to the metal tip.
• Metal or ceramic surfaces cannot be used as
touch points for the Tooth Probes. Teeth selected
for pulp testing must possess enough exposed
enamel or dentin to allow the probe to make
contact without touching the gingiva or a metal
restoration. In certain cases, this may require the
use of a Precision Probe (included).
• Fully instruct the patient as to what you will be
doing, so they are not surprised during the test.
• Tell the patient that when the vitality test is
underway, they should carefully raise their hand
at the first sign of sensing the stimulus. This
should avoid any patient discomfort.
Pulp Vitality Testing with the
Digitest II Pulp Vitality Tester
1) To activate the unit, press
and hold the start button (F) for
a half second, and then release
the button. When the button is
depressed, the display will show
one row of horizontal bars if the
device is set for “SLOW”, two
rows for “MEDIUM”, or three rows for “FAST”. When
the button is released, the display will read “00”,
indicating that it is ready to begin the vitality test.
The display will shut off if the unit is not used within
14 seconds.
2) If the desired stimulus rate
mode was displayed, the vitality
test may proceed, as detailed in
Step 4.
3) If you wish to change the
stimulus rate mode, repeatedly press and release
the button twice in quick succession. The display
will cycle between the three stimulus rate modes.
When the desired setting is displayed, press the
button one more time to let the display return to
“00”, so the test may begin.
NOTE: The unit will remember the last
stimulus rate mode setting, even if the device
is powered down.
4) Place the toothpaste-covered tip of the Tooth
Probe on the middle of the labial or lingual surface
of the tooth. Avoid soft tissue and restorations such
as crowns, amalgams or composites.
5) Depress and hold the button, and the display
number will rise, indicating that a gentle-pulse
stimulus is being automatically applied to the tooth.
When the patient indicates that they feel the stimu-
lus, release the button. The stimulus will stop im-
mediately. The display will freeze and hold the final
reading for approximately 14 seconds, so it may be
noted. The unit will then automatically turn itself off.
6) The maximum stimulus reading is 64. Even if
there is no response at this level, there is still the
possibility that the tooth is vital. No sensation at
this number simply suggests that the tooth is non-
responsive at the time of the test. However, since
teeth have been known to recover from traumatic
injury many days after presenting with a “non-vital”
reading, follow up testing is almost always indicated
after any initial readings. If this reading persists over
several visits, it is reasonable to assume that the
tooth is non-vital. However, this conclusion should
always be confirmed by another accepted endodon-
tic testing method.
7) To verify the reading, a corresponding control
tooth in the same arch should be tested. Molars
should be matched to molars, premolars to premo-
lars, cuspids to cuspids, and incisors to incisors.
If this is not possible because teeth are absent,
endodontically treated, or have full coverage resto-
rations, a similar tooth in the opposite arch should
be used.
Clinical Observations
• It is not possible to prepare a “table of normal
values” for pulp tester readings, because THERE
IS NO “NORMAL” IN PULP TESTING. Rather, the
clinician should perform sequential comparisons
between the subject tooth and the control tooth
at consecutive office visits, observing how the
readings are changing as time progresses. By
utilizing electric pulp testing, along with all avail-
able diagnostic information, it is often possible to
predict where the tooth’s vitality is heading. This
allows the clinician to make informed decisions as
to whether endodontic therapy is appropriate, and
whether it is prudent to simply watch and wait.
• There are general anatomic trends in pulp vitality
readings. Posterior teeth generally require greater
stimulus than anteriors, probably because of the
greater thickness of enamel and dentin in posterior
teeth. Enamel requires a greater stimulus than
dentin or cementum, because of the higher per-
centage of non-conductive mineral, and the lower
percentage of water. Cross-arch teeth, or oppos-
ing teeth will have similar thresholds to stimulus.
• The stimulus threshold may also be affected by
such factors as the age, gender and previous pain
history of the patient, pulp chamber size, trauma,
pathology and use of prescription and non-pre-
scription medications, or illicit drug use.
A
D
E
SLOW
MEDIUM
FAST
READY
B
Fig. 2
F
C
Continued