If this is indeed production pieces, they nailed the sculpt with a nice sharp paint finish.
Teeth shape look fine. As several others here have suggested, just needs a wash and touch up to give it a darker hue towards the bottom. This is similar to their 1/2 scale endo, sculpt and paint were great but teeth needed a wash to make it look more organic with the rest of the statue. Made a huge difference on my endo and I'm sure once done on the Chap, it'd be almost impossible to tell it apart from the prototype. Another excellent piece from Prime 1. Can't wait to get a closer look in upcoming reviews/vids of this fella.