Dan Campbell's chompers had social media talking on Sunday ... but one company is stepping up to help coach out -- offering him a lifetime supply of teeth-whitening product!!
The Detroit Lions leader's frustration was caught on cameras during the Lions' 48-42 loss to the Buffalo Bills on Dec. 15 ... and at one point, so were his not-so-pearly whites.
The shade of Campbell's teeth could be due to tobacco use or heavy coffee drinking ... and if that's the case, the folks at The White Pearl Company wants to assist in bringing his smile a few shades lighter.