>>42542926
The "teeth" that we see are inflatable patches of tissue that let something with a beak make a proper seal on a nipple. If we assume the back half is like a normal lion, that's how they can feed their cubs. It's also how they can drink from a straw with a rigid beak.

It would rely on griffs having a pneumatized skeleton, like irl birbs. Some irl birbs have inflatable pouches, but not in their beaks.

The presence of this on ordinary birds in mlp suggests they have nipples, too.