Dental amalgam is a material used to fill cavities. Fillings made with amalgam are also known as silver fillings. Over the years, concerns have been raised about the use of amalgam because it contains mercury. But it contains indium as well to retain the mercury.

Mercury is used in amalgam to make the filling material pliable. When it is mixed with an alloy powder, it creates a compound that is soft enough to mix and press into the tooth. But also hardens quickly and withstand the forces of biting and chewing.

It holds up better over time, especially in teeth that undergo a lot of pressure and wear from chewing. Compared to other materials composite resin, porcelain and gold amalgam is stronger than composite resin and require less time to restore the teeth.