That's hard to believe tbh. It takes 8+ hrs of pressure for braces to start to move teeth, these kids must be chronic gamers with a major vitamin deficiency for headphone pressure to cause dents.
I feel like a lot of other things would have the same effect, like hard hats, and bike helmets if...
Headphones usually because earbuds don't go low enough for my liking, but even my headphones are a bit loud.
Earbuds are a hassle even if they're cordless. I keep some around for travel but other than that I like my $11 headphones from Amazon. I've used them daily for about six months.