DENTAL ALLOYS FOR INDIRECT RESTORATIONS Flashcards
dental casting alloys list
gold alloys precious metal allous ni chromium alloys coblat chromium allous titanium alloys
desirable properties
biocompativkle corrosion and tarnish resistant optiumum mechanical properties bond to ceramic aesthetics cheap
RPD common matersk
cast CoCr
can be Ti alloy
- can be cast or selective laser melting
effects of high temp
high temp decreases accuracy
thermal expansion co efficient
- contracts leading to distortions in the casting
all metal restoration matERIALS
Au alloy
CoCr
NiCr
Ti
casting an all metal restoration
1) make wax pattern
2) die allows to check the margins of the model
3) take the tooth from the die with a spru
4) fill with investment material under vacuum
5) leave mould to set
6) remove refractory with acid
7) abrasives to remove the spru
8) restoration is adjusted
yield stress
when material will start to deform beyond its elastic limit
what gold alloys do we use
Au type 3/4
- increase in copper decrease in gold
less soft
why is Pd added to gold alloy
higher MP
reduce silver tarnishing
non precious metals
Ni-Cr
CoCr
Ti
produciton methods
casting
SLM production
Miliner and unsintered milling
what do bonding alloys need to be compatible on with cermaics
melting temp
thermal co expansion
must produce an oxide layer
modulus of elasticty which is compatible with the ceramic
