Dentists have used gold alloys containing platinum for many decades but the use of palladium in dentistry is relatively recent.
Dating from the 1980s, a rising gold price then encouraged palladium to be introduced as a lower-cost alternative. When the price of palladium increased sharply a few years ago this trend reversed. However, at the moment the price of palladium is lower by far than either gold or platinum and consumption of palladium in dental alloys has again increased.
Palladium is usually mixed with gold or silver as well as copper and zinc in varying ratios to produce alloys suitable for dental inlays, crowns and bridges. Small amounts of ruthenium or iridium are sometimes added. The most common application is in crowns, where the alloy forms the core onto which porcelain is bonded to build up an artificial tooth. The aim of using platinum group metals in dental alloys is to provide strength, stiffness and durability whilst the other alloyed metals provide malleability.
In Japan, the government operates a specific mandate stating that all government-subsidized dental alloys have to include a palladium content of at least 20 percent. This alloy is known as the “kinpala” alloy and is used in around 90 percent of all Japanese dental treatment. Hence, Japan is the largest palladium-consuming region for dental applications, followed by North America and then Europe.