There are systems now which will mill titanium crown-sub-structures.
Most noble porcelain to metal crowns use a platinum/palladium mix.
I have never used non-noble metals (except in temporary SSC's) since DS.

Signature
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Stephen [What's a Temporary?], D.D.S.
Michigan, USA
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This posting is intended for informational or conversational purposes only.
Always seek the opinion of a licensed dental professional before acting on
the advice or opinion expressed here. Only a dentist who has examined you
in person can diagnose your problems and make decisions which will affect
your health.
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