Teeth are normally fine, but if a problem such as not eating they need to see a Vet.
They do get a bald spots (males) on the top of their head & on their chest, so don’t panic. But if you see balding on a female or anywhere else on a male please see a Vet. Right away. (It could be a number of things.)
Keeping your cage as clean as possible will also help your glider smell less. The stress level will also help to not make them smell skunky (like they do when they get scared.)
No matter what they will smell a bit though, its just their nature to have a natural funk to them.