I think one thing is they are translucent/subsurface scattering and the enamel->dentin layer shows through underneath in kind of volumetric ways. Even lower te

I think one thing is they are translucent/subsurface scattering and the enamel->dentin layer shows through underneath in kind of volumetric ways. Even lower teeth will show through behind the tips of upper teeth a bit (with a standard overbite).