Palladium Based Alloys for Dental Applications
Posted on 09/23/2011
The use of palladium in dentistry is a rather recent event (1). As the price of gold increased in the 1980's dental labs looked for alternatives and palladium was an excellent substitute for gold.
Palladium is both stronger and harder than gold, allowing it to act as a strengthener especially popular in restorative cases involving one or more missing tooth (i.e. a bridge). Additionally, palladium has a higher melting point and a higher modulus of elasticity than gold - making it a superb alloy for porcelain baking as it can withstand high temperatures without melting.
In addition, palladium is corrosion resistant and does not tarnish, both of which are positive attributes for the wet, saliva filled environment of the mouth.
The major drawback to palladium is the silver color - it dulls the yellow color of gold considerably when alloyed with gold. As a result, patients who expect to see gold will not be satisfied with a palladium-gold substitute.
Today, as the price of palladium has increased considerably, labs face increasing pressures to use substitutes for this alloy which still conform to the Noble Metal content requirements of the ADA. Substitutes include any of the platinum group of metals including platinum, rhodium, iridium, osmium or ruthenium. However, aside from platinum, most other platinum group alloys are not ideal for dental applications as the majority metal, and are used typically in small quantities for specific purposes.
(1) More information on this topic can be found on the ADA's website: http://jada.info/content/133/6/759.full
Thanks to Marlin Gohn CDT from Argen Corporation for his memo on the uses of alloys in dental applications.
Palladium is both stronger and harder than gold, allowing it to act as a strengthener especially popular in restorative cases involving one or more missing tooth (i.e. a bridge). Additionally, palladium has a higher melting point and a higher modulus of elasticity than gold - making it a superb alloy for porcelain baking as it can withstand high temperatures without melting.
In addition, palladium is corrosion resistant and does not tarnish, both of which are positive attributes for the wet, saliva filled environment of the mouth.
The major drawback to palladium is the silver color - it dulls the yellow color of gold considerably when alloyed with gold. As a result, patients who expect to see gold will not be satisfied with a palladium-gold substitute.
Today, as the price of palladium has increased considerably, labs face increasing pressures to use substitutes for this alloy which still conform to the Noble Metal content requirements of the ADA. Substitutes include any of the platinum group of metals including platinum, rhodium, iridium, osmium or ruthenium. However, aside from platinum, most other platinum group alloys are not ideal for dental applications as the majority metal, and are used typically in small quantities for specific purposes.
(1) More information on this topic can be found on the ADA's website: http://jada.info/content/133/6/759.full
Thanks to Marlin Gohn CDT from Argen Corporation for his memo on the uses of alloys in dental applications.
Palladium, Dental Alloys, PFM, Full Cast, ADA, Noble Metal, Dental Lab Tech
- ADA Article on Biocompatibility of Dental Alloys : http://jada.info/content/133/6/759.full
