Gold teeth, or caps which originated in Brooklyn/Queens NYC back in the late 70's early 80s. Then B-more picked it up, now the Dirty South is rocking Fronts.
Gold fronts started in NY. Bust the old school spitage:
"Well that's true that's why we never have know Beef so I washed off the soap and brushed the Gold teeth" Slick Rick Ladi Dadi 1984
"I got Gold teeth and they don't chew beef" Big Daddy Kane Young Gifted and Black 1989
Old New York hip hop and urban slang for gold and platinum teeth, usually covering over actual teeth. Better known in mainstream society as a grill. Started in the 1980s and reached mainstream hip hop around 2005 when popularized by rappers like Birdman and Paul Wall.