An 18th century hand-illustrated page from an Ottoman Turk dental book showing a molar infected with toothworms. As early as Babylonian times and lasting well into the eighteenth century, it was thought that a toothache was caused by worms. (The theory was disproved by Jacob Christian Schaffer in 1757.) These worms were depicted in art as dwelling with the demons of Hell and feeding upon the sinners. In a cavity on one side of the bisected tooth, Lucifer watches as two worms devour and entrap their victims. In the other half of the tooth, demons lord over a collection of human skulls.