Perfumed polymers can be made into round rings that can be worn on the teeth. This will help to reduce the effect of mouth odor or even overshadow it completely. The polymer will be so slim that it will not discomfort the wearer's mouth. It will also have to be made of hypoallergenic materials. It can also be laced with medication that will improve the wearer's dental health in the long run.
The material used will be preferably transparent or they can be white and translucent so that they seem to create a whitening effect too. They should also be perforated so that they let you brush your teeth without having to remove them, this will reduce the chance of forgetting to put them back on or losing them.
This type of "mouth freshener" does not have to be used by people who have bad breath alone. It can be marketized to the extent where there will be luxurious brands that use it to compliment their fancy bodyspray products.
More fashionable versions of the product can be made to have silver or gold colors. Children will also like versions that have images of their favorite cartoon characters. They can be customizable so that you chose what is printed on your "mouth freshner."
They can also be used as a means to administer medications that are required in small amounts.They can be modified to fit on the teeth of pets too.