Noble dental alloy
A dental prosthesis may be cast and machined from a cobalt-, iron- and/or nickel-chromium base dental alloy comprising at least 25% metal selected from the group consisting of ruthenium, platinum, palladium, iridium, osmium, rhodium, and gold wherein the major portion or at least 15%, whichever is larger, of metal in this group is ruthenium; from 15 to 30% chromium; and a principal balance of metal selected from the group consisting of iron. nickel and cobalt.
1. A dental alloy comprising:
at least 25 wt % of at least one metal selected from the group consisting of ruthenium, platinum, palladium, iridium, osmium, rhodium, and gold provided more than 15 wt % of the total dental alloy composition is ruthenium;
15 to 30 wt % chromium;
5 to 15 wt % gallium such that the alloy can be melted with a natural gas- or propane-oxygen torch; and
at least 40 wt % of cobalt.
2. A dental alloy according to claim 1 further comprising up to 5 wt % silicon and/or up to 1 wt % boron.
3. A dental alloy according to claim 1 further comprising up to 5 wt % of a metal selected from the group consisting of niobium, tantalum and rhenium.
4. A dental prosthesis including an alloy comprising:
at least 25 wt % of at least one metal selected from the group consisting of ruthenium, platinum, palladium, iridium, osmium, rhodium, and gold provided more than 15 wt % of the total dental alloy composition is ruthenium;
from 15 to 30 wt % chromium;
5 to 15 wt % gallium such that the alloy can be melted with a natural gas- or propane-oxygen torch; and
at least 40 wt % of cobalt.
5. A dental prosthesis according to claim 4 further comprising up to 5 wt % silicon and/or up to 1 wt % boron.
6. A dental prosthesis according to claim 4 further comprising up to 5 wt % of a metal selected from the group consisting of niobium, tantalum and rhenium.
7. A blank for machining a dental prosthesis including an alloy comprising:
at least 25 wt % of at least one metal selected from the group consisting of ruthenium, platinum, palladium, iridium, osmium, rhodium, and gold provided more than 15 wt % of the total dental alloy composition is ruthenium;
from 15 to 30 wt % chromium;
5 to 15 wt % gallium such that the alloy can be melted with a natural gas- or propane-oxygen torch; and
at least 40 wt % of cobalt.
8. A blank for machining a dental prosthesis according to claim 7 wherein the alloy further comprising up to 5 wt % silicon and/or up to 1 wt % boron.
9. A blank for machining a dental prosthesis according to claim 7 wherein the alloy further comprises up to 5 wt % of a metal selected from the group consisting of niobium, tantalum and rhenium.