DENTIST, n. A prestidigitator who, putting metal into your mouth, pulls coins out of your pocket.

Ambrose Bierce (1842-1914?) American writer and journalist
“Dentist,” The Cynic’s Word Book (1906)
    (Source)

Included in The Devil's Dictionary (1911). Originally published in the "Devil's Dictionary" column in the San Francisco Wasp (1882-02-17).