I once read a Native American Ponca-Otoe story about women with teeth in their vaginas. They were cursed by an old witch who made them seduce men and kill them by gnawing their dicks off. One of the girls didn't want to do it anymore so Coyote killed the witch and the evil girl who liked killing men, and then knocked out all the teeth from her vagina, but "left in a blunt one that was very thrilling when making love".
Seriously. I'm not making this up, I swear.
Edit: Holy smokes, look at this link!
Teeth in the Wrong Places combines the narration of a Ponca-Otoe Native American folktale with a slow, time-based performance. As the story unfolds of Coyote’s seduction by two young women with gnashing teeth in their vaginas, a richly alluring mouth slowly chews and regurgitates material. The performer’s gaze with the audience is one of controlled temptation and latent violence. The undermining of traditional narratives of power leak through the film via ironic humour and magnetic confrontations with the audience.
"Teeth" is part of the installation “La Specola: medical examination & archetypes of the vagina dentata,” which employs video narratives, surveillance cameras and a computerized, 3D interactive vagina to address the mingling of myth and medicine in gynecology. Jiggly, tactile latex sculptures and cloying beeswax panels position viewers' bodies within the installation, provoking visceral responses to reveal our cultural conditioning to the abject, the pleasurable, and the taboo.