Hunter-gatherers wear down their teeth considerably and consequently had bigger jaws. I'm wondering if chewing gum really has the same effect on jaw development as eating hard foods. Is it correct to assume that "hard" gum doesn't really wear down the teeth because it isn't really hard but rather chewy?
any sort of pressure against the tips of the teeth is going to be good, but yes; ripping food from the incisors like jerky and tough bread is going to be best. that stuff is like sandpaper
Simply wearing teeth down in and of itself doesn't help facial aesthetics. Especially if you are a guy. Wear your teeth down and your lower third becomes much shorter. It happened to Kurt Cobain. Great mandible development but his short lower third made him look androgynous. Bruxism accomplishes the same. As does edge to edge biting.
But anyway the goal shouldn't be to overwork the jaw. That leads to TMJ eventually. Postural change in and of itself is the healthy way to go but without the side effects.
Wearing down the teeth just to wear them down is not healthy. You definitely want your teeth fully functioning and strong into old age.
The goal is postural change and facial development and never just wearing down the teeth. Otherwise bite on ice cubes and wear your teeth down if you really want to.