Well, for the most part, people don't actively check all of their chin's teeth. The back molars would be hard to see without the help of a vet.
You can see their incisors though when they chew on a stick or yawn. That's the easiest way to see them. Just wait until you catch a glimpse of them, they should be dark yellow/orange, not white.
If your chin doesn't mind having it's chin scratched you can feel along their jaw and if you do it often enough, you'll be able to feel any abnormalities should they arise, like a bump which may indicate roots elongating.
I know that you can open a chin's mouth to see the incisors, but I wouldn't do that to my girls. You can just see their front teeth normally every once in a while.