“When is the best time for a dental appointment?”/“Tooth-hurty (2:30).”

A classic dentist joke is:
 
Q: When is the best time for a dental appointment?
A: Tooth-hurty (2:30 ).
 
The “tooth-hurty”/“2:30” pun has been cited since at least October 1877, when it was printed in many American newspapers. The joke has been associated with Chinese Pidgin English since at least 1937.
 
       
14 October 1877, Detroit (MI) Free Press, pg. 5, col. 7:
The Editor of the Franklin (Ky.) Patriot says that when he started for the dentist’s the other day, he took a tooth-hurty gait
 
Chronicling America
24 October 1877, Alpena (MI) Weekly Argus, “Select and Original,” pg. 4, col. 1:
The editor of the Franklin (Ky.) Patriot says that when he started for the dentist’s the other day, he took a tooth-hurty gait.
 
Google Books
February 1902, The Dental Digest (Chicago, IL), pg. 170:
RACY.—When a man starts for a dentist’s office he usually strikes a tooth-hurty gait.
     
Google Books
National Dental Hospital Gazette
Volume 4
1937
Pg. 124:
The Intricacies of Pidgin English.
 
Chinaman (on the ‘phone): “Can you extract a tooth for me this afternoon?”
Dentist: “Yes, certainly. Two-thirty?”
Chinaman: “Yes. Tooth hurty, vellee much.”
 
Google News Archive
14 November 1947, Sarasota (FL) Herald-Tribune, pg. 4, col. 6:
PAINFUL ANSWER…Said one small girl to another…“What time do you have to go to the dentist?”
 
“Tooth-hurty this afternoon,” was the answer. 
 
Google News Archive
2 April 1955, Reading (PA) Eagle, “Comedy Hour May Originate in Las Vegas in Test Move” by Atra Baer (INS), pg. 6, col. 5:
He (Marlon Brando—ed.) also told a joke: “What time is it when the Chinaman goes to the dentist?” Murrow said he’d bite. “Two-thirty. Tooth-hurty. Get i?” Brando grinned.
 
Google News Archive
18 January 1965, The Free Lance-Star (Fredericksburg, VA), “Fun Time—The Riddle Box,” pg. 12, col. 2:
What time do most people go to the dentist?
At tooth-hurty.
 
Google News Archive
8 February 1969, Baltimore (MD) Afro-American, “Dentist’s office plagued by unwanted night visits” by Adam Kline, pg. 32, col. 5:
“What’s the best time of day to go to the dentist?”
 
“Why, at tooth-hurty, of course!”
   
Google News Archive
22-28 August 1989, Mohave Daily Miner (Kingman, AZ), Mohave County Weekender, pg. 16, col. 1:
When is it time to visit the dentist? Tooth-hurty, of course
BY WENDY MILLER
 
Google Groups: alt.astrology
Best time for a dental appointment: Tooth hurty
Keera A. Fox
10/17/01
Dell “Horoscope” says in its October issue:
 
Twitter
Darren E. Draper
‏@ddraper
I have a dentist appointment today. First cavity in 16 years. My appointment is at 2:40, but I was hoping for tooth-hurty.
2:57 PM - 3 Dec 2007
 
Urban Dictionary
tooth hurty
the universal time to go to the dentist
Peter planned to go to the dentist at tooth hurty.
#time #tooth #teeth #dentist #cavity
by sheila in the car March 14, 2010
 
Urban Dictionary
Chinese dentist time
The name given to the time 2:30 this is because if a Chinese person says “two-thirty” it sounds like they’re saying “tooth hurty”.
It’s Chinese dentist time.
#chinese #dentist #time #cowboy time #pi time
by carbona not glue November 02, 2010
 
Google Books
Insults Anywhere Kids Presents
Hundreds Of Kids Jokes They Can Tell Anywhere!
By Franklin Yantz
Insults Anywhere at Smashwords
2011
Pg. ?:
Q: What time do you go to the dentist?
A: Tooth-Hurty!
 
Google Books
The Ultimate Kid’s Joke Book
By Peter Coup
London: Arcturus Publishing Limited
2013
Pg. ?:
What time do you go to the dentist?
Tooth-hurty!