t/f with admix you use less condensation pressure because it has little resistance
which establishes a contact easier admix or spherical?
what must be done to get a contact with spherical?
t/f admix uses more mercury
t/f spherical has high early compressive strength (1 to 24 hours)
t/f spherical uses 10% more mercury
FALSE, 10% LESS
which has a slower set admix or spherical..think about it, I am going to make you think...pause pause pause
admix-it has a longer working time
t/f spherical has a faster set time?
true dat mhm
at 24 hours both admixed and spherical ____ copper amalgams shrink slightly whereas ____ copper amalgmas expand
____ is the mixing of powder and mercury
what is the appearance of a properly triturated capsule?
what is the appearance of an UNDER triturated amalgam
dry crumbly and sets too quickly=weak filling
t/f an under triturated amalgam results in a weak filling
if the amalgam is dry crumbly and sets quickly is it:
A. properly triturated
B. over triturated
C. under triturated
C. under triturated
what is the appearnace of an OVER triturated amalgam
too wet, sets too quckly and is a weak filling
t/f amalgam that is too wet and sets quickly is under triturated
false OVER triturated
why should you overfilll a cavity prep with amalgam?
to allow enough material to carve contours and remove excess mercury that is forced to the surface by condensation
t/f carving amalgam after set starts will damage the margins
how long must the pt wait to eat on an amalgam restoration?
what % of strength does the amalgam have at 8 hours?
what % of strength is the amalgam at after 1 hour of set up?
what % of strenght is the amalgam after 24 hours of set up?
100% DING DING DING all done!
when should an amalgam be polished?
24 hours after placement
t/f polishing should not be done earlier than 24 hours after placement
____, _____ copper alloys need no polishing
t/f Modern, high copper alloys are dull and need to be polished to shine
FALSE, the are shiny and need no polishing
How is polishing of an amalgam done? (hint what must you use 2 things...man I am so thirsty think I will go drink me a little WATER)
what three things retain amalgams in preparation?
under cut walls
irregularities in tooth wall
what is the process if amalgams are bonded into the preparation?
etched iwth phosphoric acid
one or two bonding resins placed
Amalgam applied to WET chemical cured resin
t/f when amalgams are bonded in the amalgam is condensed onto a dry chemical cured resin
FALSE...Wet chemical cured resin (go get Jade she is good at getting Analey wet she can help here..wait...oops)
what must be used when placing an amalgam to help minimize swallowing amalgam particlees or inhaling released amalgam vapors? 2
high volume evacuation
what is the OSHA acceptable mercury exposure level?
.0005 mg/m3 for 40 hr work week
t/f most dental offices are close to exceeding OSHA acceptable mercury exposure levels
FALSE! most are far BELOW recommened levels
what degree is mercury vapors released?
80 degrees C
how is scrap mercury stored?
under water in airtight container
t/f you operatories should have no carpet or tiled floors for mercury safety
T/F mercury free amalgam is no longer used in USA
True..but why? read the paragraph it will tell you!
dental amalgams STARTS AT HANDLING CHARACTERISTICS