Nothing grows on a dry tooth 

Nothing grows on a dry tooth is an old Canadian idiom. It means that being bitter and closed off can't lead to any change/making new friends. Saying it is a good way to call out your friends out when they display un-Canadian-like behaviour.

Can I have a bite of your pancake?
No.
Nothing grows on a dry tooth.

Nothing grows on a dry tooth by Gotzzz July 31, 2016