I think I put a previous idea transparent henna
sunscreen up here. This is really similar only it freshens
Imagine the henna molecule modified to be perfumed or
deodorizing. Swish it around your mouth and your cheeks
and tongue stay coated producing a couple months of
you do not need the henna. Henna attaches
to tissue with something called the michael reaction
[link] so many other molecules, preferably transparent
and neutral flavored could do it. Link those molecules to
a perfume or possibly something like the polystarch
febreze to sweeten the breath.
This could be a once a month mouthwash or even a
Swish it around your mouth and your tongue and cheeks
coated with a breath deodorizer or perfume. Perhaps
doses could be put in toothpase, so your breath is
cumulatively fresher the more you use.