Animal whose horns penetrate its skull?

Question

There's an animal whose horns grow from its snout only to curve back and eventually penetrate its skull... does anyone know the name of this animal?

Answer 1

Are you sure you mean horns?
In babirusa hogs (relatives of wild boars), the tusks (greatly enlarged canine teeth) grow upwards describing a curve, they pierce the snout of the animal and continue to grow until they're near the frontal part of the skull. However, these are teeth, not horns.
http://www.oregonzoo.org/images/Babirusa.jpg

See this site to see if this is what you're talking about:
http://animaldiversity.ummz.umich.edu/site/accounts/information/Babyrousa_babyrussa.html

Answer 2

I don't know this one. However, I just recently read that the horns of the horny toad (aka the horned lizard) are actually not horns but are extensions of the actual skull.

Answer 3

I think that's a sort of boar...