Ultrasonic Intrumentations Flashcards
what instruments should be used supragingivially?
scalers, and mcalls
what is the mcalls 13/14 used for?
bicuspids
what is the mcalls 17/18 used for?
molars
what can the ultrasonic be used for?
calculus necrotized ulcerative gingivitis overhanging restorations excess cement stains
what types of powered scalers are there?
sonic and ultrasonic
whats the frequency of the powered scalers
sonic: 6000 hz
ultrasonic: 20-50000 Hz
what types of ultrasonic scalers are there?
magnetostrictive and peizoelectric
what direction does the tip of an sonic scaler move?
elliptical
what are some disadvantages of the sonic scaler?
heats the tissue so needs to be cooled and cant remove heavy deposits
how is the peizoelectric scaler powered?
alternating current to reactive crystals
what direction do peizoelectric scalers tips move?
linear, therefore only two sides are active
magnetostrictive tip moves in what direction?
elliptical
MS scaler similar to sonic, makes heat, elliptical
how is the MS scaler powered
ferromagnetic stacks
how do ultrasonic scalers clean teeth?
1) by disrupting bioflim, otherwise known as deplaquing
2) cavitation bubbles: expansion and collapse of bubbles a formation of radicals
what are some advantages of ultrasonic scalers over hand scaling?
less time more comfort less stress on the hand technically less demanding no sharpening
what are some advantages of hand scaling over ultrasonic scalers?
more visibility more tactile sensitivity no aerosols better subgingivally easier on the roots no irrigation
the water suppy can be easily contaminated, what are some things that can be one to prevent contamination?
self-contained reservoir
point-of-use filter
flushing the tube
how should the tube be flushed?
2 min at the start of the day and 30 sec before each use
why is the ultrasonic handpeice filled with water before inserting the scaler?
to remove air bubbles; air bubbles can cause it to overheat
how do you adjust the water setting?
make sure the power is on a low setting
what is the out of phase setting and when should it be used?
its a steady drip of water and it should be used on light deposits
would should be the water setting for heavy deposits?
maximum efficiency: mist
T or F
water level must be changed every time the power setting is changed AND when the tip is changed.
true
when should the USS be used on the high setting?
pretty much never, medium power is good enough
The boost mode increases ______ by _____ percent
water flow
amplitude
frequency
power
10
15
20
25
power (technically amplitude and frequency is good enough too)
25
T or F
the proper way to use the USS is to apply pressure against the calculus.
F
applying too much pressure dampens the vibrations, use light strokes
what kind of tips are there for USS?
thin for light deposits heavy for heavy deposits subgingival implants: PLASTIC TIP furcations
what are the surfaces for the tip?
lateral
face
back
point
what surfaces are used to remove calculus?
lateral and back
which surface is most effective?
lateral
face
back
point
lateral
whats the power distribution of the surfaces?
lateral
face
back
point
point>face>lateral>back
when can the point be used?
to fracture large deposits
how is the USS and curette similar when it comes to adaptation?
Transverse orientation: lateral surface adapted above or just below the gingival margin
how is the USS and probe similar when it comes to adaptation?
vertical orientation: lateral surface adapted below the gingival margin
How is the USS and currette used differently when it comes to removing calculus
curettes remove bottom up, USS remove by crushing it top down
how does the tip remove calculus?
by creating microfractures
match:
tapping stroke
sweeping motion
light deposit
heavy deposit
deplaquing
tapping stroke= heavy
sweeping= light
sweeping= deplaquing
where are the aerosols getting contaminated from?
usually rebounded off the patient
what can be done to reduce contamination from the patient?
preprocedural rinse
barrier protection for both you AND the patient
high volume evacuation
the power knob adjusts _____
amplitude
frequency
both (overall power)
amplitude: length of the stroke
what is a sign of inadequate water being used?
heated handpeice
T or F
its better to use more water than less water
T
what is the advantage of using a 30k Hz over a 25k Hz magnetostrictive scaler?
more efficient in removing deposits
more efficient in power usage
creates less noise
creates less noise
practically no difference overwise
which one of these are NOT patient contraindications to the use of USS?
unshielded pacemaker uncontrolled diabetes TB immunosuppressed chronic pulmonary disease asthma children difficulty breathing all are contraindications
uncontrolled diabetes
which one of these are NOT tooth contraindications to the use of USS?
porcelain gold amalgam composite demineralized teeth implants all are contraindications
all are contraindications
how much wear must the tip wear out for it to be thrown out?
2 mm
how less effective is 1 mm or wear? 2 mm of wear?
25% - 50%
where is the power concentrated in the handpeice?
last 2-4 mm of the tip
how do you measure the wear of the tip?
Hu-Freidy guide
T or F
the beavertail tip is used supra and subgingivally and is used to remove large deposits and stains.
F, not subgingivally everything else is true
T or F
the standard Diameter universal tip is used supra and subgingivally near the margin.
T
T or F
slim diameter straight tip can be used throughout any depth in a pocket but does not adapt well to the curved surfaces of posterior teeth?
F, only to a depth of 4 mm, rest is true
what can be used to adapt to the curvature of post. teeth?
the curved slim tip
which tip can be used a depths greater than 4 mm?
the curved slim tip
which tip is best used for furcations?
slim diameter straight tip
curved slim tip
beavertail tip
standard Diameter universal tip
curved slim tip
T or F
for best tactile feedback, the instrument should be on
F
T or F
its better to used a ball tip rather than a curette to remove calculus in furcations.
T, adapts to the curvature better
how is the fluid controlled during the use of instrumentation?
widen vestibule for posterior
pull lower lip for anterior teeth
