exam 2 Flashcards
(26 cards)
powered instrumentation devices
use a rapidly vibrating irrigated working-end to dislodge calculus, etc.
what 2 types of ultrasonic are there
piezo and magneto
sonic powered devices
lower frequency
air driven
tip moves circular
attach directly to hand piece
piezo devices
electrical energy to activate crystals within the hand piece to vibrate tip
only active on lateral sides
magneto devices
transfer electrical energy to metal stacks made of nickle-iron alloy or to a ferrous road to vibrate the insert
all surfaces active
what kilohertz option do we have on our unit
30K
cavitation
formation of tiny bubbles when the water stream contacts the vibrating working end
frequency
measure of how many times a powered working-end vibrates per second
amplitude
measure of how far the powered working-end moves back and forth
what pattern does a magneto move
elliptical (circular)
what pattern does a piezo move
primarily linear
do sonic tips overheat
no
1 mm of wear results to approximately how much less efficiency
25%
what mm measurement should you discard the instrument
2mm
advanced fulcrum
good for powered instrumentation
cross arch, extraorally, opposite arch
where do you start with powered instrumentation
coronally to apically
strokes for calculus removal with a power instrument
gentle pressure
slower, repetitive strokes
overlapping
should the powered instrument working end be moving at all times
YES
active tip area of a powered instrument
2-4 mm
amount of energy dispersed in order
point of tip
concave face
convex back
lateral surfaces
transverse tip orientation
active surface in a transverse orientation to the long axis of the tooth
vertical tip orientation
active surface against the tooth surface
like probing
tip angulation for powered instruments
0-15 degrees
coronal polishing
a cosmetic procedure designed to remove stains
