ve heard that resin has been used as chewing gum for many hundred years.
Here you can read about it: http://en.wikipedia.org/wiki/Chewing_gum,
I know they sell chewing gum made of resin in some norwegian health shops. So Im sure you can find them in health shops in your country as well.
I have never tried it, so I don`t have any idea how it tastes.
Well, my dentist recommended that I chew gum because my mouth was a little more dry than he could like. I like the taste of xylitol gum and I've gotten along well with it in the past plus the dentist was happy with my choice.
I don't consider it paleo, but it is my favorite. I buy it at my local "health" store (quotes used because they have a generous share of junk there) and read the label to avoid the worst additives.