Brazilian agency Africa pulled off a fun stunt to promote Oral B 3D White superior whitening power last weekend. At an Ultimate Fighting Championship (UFC) event held in the UK, bantamweight champion Renan Barao entered the arena with a dazzling white smile thanks to an LED mouthguard, then promoted the brand via Twitter. Retweets and other social media in Brazil apparently skyrocketed as a result. Some 30 million Brazilians now watch UFC events on TV. Ryan Lochte better get in on this one.