Mike 'Sugar Bear' Thompson's Dentist Discovers Possible Cancer During Makeover

Sugar Bear's makeover could be life-changing in more ways than one ... because a dentist discovered what appears to be a type of cancer in his mouth.

A rep for Suge tells TMZ ... the reality TV star is undergoing a full makeover in Los Angeles, and when he went to a dentist Thursday to get new teeth, the dentist found what looks like possible cancer of the lower gums.

We're told the signs of potential cancer include multiple white spots on Sugar Bear's gums.

Sugar Bear was a chewing tobacco enthusiast for at least a dozen years, which we're told ended up rotting his teeth and may have now caused far greater damage.

Sugar Bear, who is the father to Honey Boo Boo and was once engaged to Mama June, was getting a makeover after finalizing a divorce ... we're told he wants to be new and improved for potential suitors now that he's single. SB recently turned 50 and wanted to boost his confidence as well.

We're told Sugar Bear's self-esteem was on the rise after he started the makeover, which also included a hair transplant, Botox, filler, liposuction, tummy tuck, a new haircut and a fresh shave ... but now the potential cancer discovery has his him gutted.