There's a Kickstarter going right now for an invention called the PIZZA FORK. And basically, it's a pizza cutter with a fork on the end. If you want one, you can pledge $10 or get four of them for $25.
https://www.kickstarter.com/projects/1899891666/pizza-fork Stupidiotic Pizza Fork.
The best practices for pizza-eating are fairly simple: Use your hands; try to keep your mouth closed; fold, if you're into that; and don't stop until you're physically uncomfortable. Nowhere in the above list is a fork mentioned. This is not an omission.