Ivory was still used for the base of dentures in the 1800s, even after quality human teeth became more available near the end of the 18th century. The best dentures were made from human teeth. The source of these teeth ranged from robbed graves, peasants looking to make a quick buck, and even dentists' collections. Commonly made of hippopotamus or walrus ivory, this kind of denture was only affordable to the wealthy. The addition of human teeth was designed to give a more realistic look. These teeth were harvested from mortuaries and later battlefields and became known as Waterloo teeth.