Derek Laskie writes:
This is a photo of a wooden pail full of teeth which Painless Parker extracted.
Edgar R R 'Painless' Parker is described: 'heavyweight champion of tooth pullers died in 1952 at age 80' The American Dental Association called him 'a menace to the dignity of the profession'. It seems that he was a bit of a huckster/showman, wearing a necklace of human teeth and making a fortune.
You can read more about Painless Parker at www.ushistory.org.