“Say aah.” Use this phrase (or another of your choosing) to teach your pug to open his mouth on command.
Lift his lips to check the teeth for tartar buildup.
While you’re at it, make sure the gums are nice and pink.
When you push on the gums, they should go white and then regain color rapidly.
Pale gums are a sign of many serious problems, including bloat, poisoning, and parasite infestation.