Literal:
* The vampire bared its fangs and hissed menacingly.
* The snake used its fangs to inject venom into its prey.
* The tiger's fangs were as sharp as knives.
Figurative:
* The critic's words were fangs aimed at the author's heart.
* The lawyer used his fangs to tear apart the witness's testimony.
* The gossip columnist wielded her fangs with deadly accuracy.
Humorous:
* My cat's fangs are adorable, even when they're digging into my arm.
* I'm not sure what's more terrifying, the clown's smile or his fangs.
* After eating garlic, the vampire's fangs were quite sore.
The best way to use "fangs" in a sentence depends on the context and your intended meaning.