From YahooNews: 

Texas school district bans grillz

ARLINGTON, Texas - The school district here has expanded its dress codes to include mouths — and earlobes.
 
Students may no longer wear mouth jewelry known as “grillz” — shiny teeth caps — or the earlobe-stretching practice known as “gauging.”

“The district is having to respond to fads because they’ve become distracters or a safety hazard for those around them,” said Malcolm Turner, the district’s executive director of student services.

The nearby Irving, Grand Prairie and DeSoto districts also ban grillz, and some also address gauging — the process of placing increasingly large items in the ears to stretch the lobes.

But students said the body modification is simply self-expression.

“Really, a grill is just like an earring. It’s fashion,” said junior Devonte Wright, 16.

(more here)