What is the difference between toric contacts lenses and regular contact lenses?

[Weingarten]

my sister and i both wear contact lenses. Mine are regular and hers are toric. We have notice that hers are a lot more expensive that mine. What is the difference?

[Weippe]

Toric lenses are for an astigmatism perscription as well as short-sighted. Toric contact lenses are made from the same materials as regular contact lenses, so they can be either soft or RGP. The difference is in the design of the lens. Toric lenses have two powers in them, created with curvatures at different angles (one for astigmatism, the other for either myopia or hyperopia). There's also a mechanism to keep the contact lens relatively stable on the eye when you blink or look around. To provide crisp vision, toric contact lenses cannot rotate on your eye.Toric lenses are weighted so that they hold their shape without conforming to the surface of the eye, which is how they correct astigmatism. Normal lenses do not do this, and will lie smooth to the surface of your cornea; because of this, they will not correct your astigmatism, and you will not be able to see properly.