When someone says to you “I think my teeth are dull”, your conditioned response is “you should have them whitened”. This is good advice only when the individual it is directed at is not commenting on the actual ability of his teeth to puncture and cut things. If one is worried about whether ones teeth are in prime condition to eat through a living rhino, this may be a legitimate concern. For this or any number of bizarre reasons, it is possible to have your teeth filed into sharpened points. In places like Bali and Sudan, people filed their teeth into points as part of a tribal practice as a rite of passage, adornment, or simply because it was extremely frightening. The Wapare of intertropical Africa do it to imitate sharks. The practice persists today, usually as part of the general milieu of cosmetic body modification. And you can too. Displeased with the fact that you, as an omnivore, have an assortment of teeth for a variety of specialized tasks? No problem! Have them all permanently filed into scary, impractical fangs!