How does a dog who licks its butt all day and eats cat crap and dirt have the cleanest mouth in the world?

Answer 1

Well it doesn't. It might not have bad breath, but there's all sorts of things lurking in it's gob just waiting to get at me an you :-)

Answer 2

Their saliva acts kind of like an antiseptic, killing germs and bacteria. That is not to say their mouths are the "cleanest mouth in the world", but their saliva certainly helps keep it clean for the most part.

Edit: Scientific findings:
"In a 1990 study done at the University of California, Davis, researchers found dog saliva killed E. coli and Streptococcus canis, another harmful bacteria. The scientists concluded that when mother dogs licked their nipples it helped keep puppies free from disease, and that dogs licking their own wounds accomplished the same goal".

Answer 3

They don't. I read an article in the paper a while back that addressed this misconception. Their mouth is just as dirty as ours. The dogs and we have different bacteria and most cannot be transfered to the other.

Answer 4

they arent the CLEANEST..but neither are peoples mouths.
and yeah..listen to alex. he makes a good point.