Dental gold varies in both karat and alloying materials. It is
engineered, since the 60’s I would think, to cast well, with minimal
shrinkage and with a “micro refined” grain structure. This refined
grain structure yields a dense casting that is less prone to pitting
When I made crowns and bridges years ago, the dentists sometimes
specified gold occlusal surfaces–the biting surface-- for crowns
such as molars that would recieve porcelain on their facial or buccal
surfaces, since gold, while perhaps cosmetically less appealing than
tooth- like porcelain (this was before the age of bling), was kinder
to the opposing dentition and so less likely to wear the upper or
lower molar down.
The mouth is a pretty hostile environment to metals. Saliva can act
as an electrolyte or even a mild etchant. Castings that had shrink
spot porosity or spongy structure quickly discolored and became
Many of the yellow gold alloys that I worked with were somewhere in
the 16k range. Many of the alloys did, indeed, contain palladium.
(Although I can’t recall the casting temp. to be much higher than
similar jewelry alloys.) Different alloys were engineered for
different applications. Alloys designed for use with certain types of
bridgework were rigid and stiff, the better to hold any porcelain
that might be applied to the surface. Full coverage gold crowns were
cast in gold that was fairly “noble” and non reactive with malleable
margins (the thin place where the crown met the remaining tooth prep)
that could be burnished down to seal the crown against saliva and
So, all dental golds are not created equal. One thing to remember is
that all metals in the mouth are not necessarily gold. Any white
metal I would look on with suspicion. Porcelain single crowns that
are built around a white metal coping may be a special nonprecious
alloy that may contain chrome, etc.
I have recast and even rolled down yellow dental gold in the past
without many problems. It all depends on what the alloy is. One thing
to consider is if you have enough gold to include a button and
sprues. I had a reserve of mystery gold of similar karat that I would
use to make up the weight for any gating, etc. I didn’t like to
consign any of my “known” gold alloys to the mystery melt.
Good luck and give it a try.