Floyd Mayweather can't help but surround himself with money. It's on his bed, on his birthday cake and, now, in his mouth.

TMZ is reporting that Mayweather, who is preparing for a May 2 megabout with Manny Pacquiao, pays roughly $25,000 for each of his custom-made mouthguards.

So, why does Mayweather drop a fortune on these mouthguards? The undefeated 38-year-old likes to customize them with lavish details, like gold flakes and diamonds. He also apparently likes putting real $100 bills inside the mouthguards.

Mayweather gets his mouthguards from Dr. Lee Gause, a dentist in New York City who often flies out to Las Vegas before Mayweather's fights to make sure the mouthguard fits. Mayweather says Gause's mouthguards help him breathe better.

Congrats to TBE Floyd Mayweather - #iceberg #tmt #tbe #hardworkdedication

A photo posted by Lee Gause DDS (@smiledesignmanhattan) on

The pair connected before Mayweather's 2012 bout with Miguel Cotto and have been together ever since.

"Athletes don’t like mouthguards because they can’t breathe with them," Gause told the New York Daily News. "If you watch the Cotto fight, you’ll see he pops his mouthguard out about 15 times. Then you see Floyd, and he drinks water with it in, talks to his trainer in the corner. He never pops it out during the competition."

It's a good thing Mayweather is extraordinarily wealthy, because his preparation for the Pacquiao fight could set him back hundreds of thousands of dollars. In addition to customized mouthguards, Mayweather is dropping serious coin on his meals in the leadup to the fight. TMZ reported that Mayweather has been paying his personal chef $1,000 a meal, which could amount to as much as $184,000.

But Mayweather has never been especially stingy, and when it comes to protecting his teeth, he has his priorities in order.

"My career's gone on 19 years," Mayweather told TMZ, "and I've been able to preserve my smile."

Mayweather, who is worth $250 million and is already the highest paid athlete in the world, is expected to take in around $180 million from the upcoming fight.

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