Four years ago hip-hop artist Lil Jon asked custom jeweler Jason Arasheben to make him something that was truly one-of-a-kind.

FORBES

Soap actress Lisa Rinna, supermodel Niki Taylor, rapper Lil Jon, country singer John Rich and model Hope Dworaczyk complete the line-up.

BBC: Meat Loaf and La Toya set for US Celebrity Apprentice

Artists like Ludacris and Lil Jon have been snapped wearing grills, also called fronts--typically gem-coated mouthpieces that slide over the teeth like tricked-out dentures.

FORBES: The Most Eye-Popping Celebrity Bling