“Why did the pie go to the dentist?”/“To get a filling.”

A popular pie joke on National Pie Day (January 23), Pi Day (March 14) and Thanksgiving (November) is:
 
Q: Why did he pie go to the dentist?
A: To get a filling.
 
The joke has been cited in print since at least 1989 and has been printed on ecards.
 
“Why did the Oreo go to the dentist?”/“Because it lost its filling.” is a similar joke.
     
 
Google Books
Riddle Roundup:
A Wild Bunch to Beef Up Your Word Power
By Giulio Maestro
New York, NY: Clarion Books
1989
Pg. 14:
Why did the pie shell go to the dentist?
To have his cavity filled,
 
Google Books
Jokelopedia:
The Biggest, Best, Silliest, Dumbest, Joke Book Ever
Edited by Ilana Weitzman
New York, NY: Workman Publishing Company, Inc.
2006
Pg. 217:
Why did the pie crust go to the dentist?
ft needed a filling.
 
Google Books
Let’s Eat in the Funny Zone
By Gary Chmielewski
Chicago, IL: Norwood House Press
2008
Pg. 20:
Why did the pie crust go to the dentist?
It needed a filling!
 
Twitter
Sophie Morton
‏@_SophieMorton
Joke of the day: Why did the pie go to the dentist? To get a filling. #cheezfriday The bad jokes are back, folks.
2:00 PM - 16 Oct 2009
 
Someecards
March 14, 2012
Why did the pie go to the Dentist?
Because it needed a filling!
Happy Pi Day!!!
 
Google Books
April Fool’s Day Jokes to Tickle Your Funny Bone
By Amelia LaRoche
Berkeley Heights, NJ: Enslow Publishers, Inc.
2013
Pg. 39:
Why did the pie go to the dentist’s office?
It needed a filling.
 
reddit
Why did the pie go to the dentist? (self.cleanjokes)
submitted October 8. 2015 by peacecake
It needed a filling.