Painless dentists

Hi,

I'm trying to understand the expression "a painless dentist" as in the following sentence:
"The man had a little, pointed, brown and grey beard, like that of a painless dentist." O Henry.

Thanks

Jean-Luc

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In the late 19th century, when O. Henry made this little joke, anesthesia was still relatively new, and being a "painless" dentist was still a distinction. His description paints a picture of a small, somewhat officious practitioner. It's the cliche look, much as we might picture a psychiatrist (with the obligatory beard) today.