From browsing the internet for a solution to this "smelly" problem it seems that it is a problem for a lot of people, not just me.
I wear a mouth guard (to prevent teeth grinding) at night and one yucky thing that happens is that it gets quite dirty - stained - and even worse very stinky!!!!
The staining I can handle. But the smell is really unbearable.
There doesn't seem to be one failsafe cleaning solution available on the internet. A lot of the items like soaking in denture solution or mouthwash cannot be be used longterm as it damages the guard.
So here is what I have come up with!
1. Give it a quick rub over with toothbrush and toothpaste every morning
2. Give it a good scrub once a week with toothbrush and toothpaste
3. Store it in water every day i.e. it's either in your mouth or in water
And finally my NEW suggestion (I did not see this anywhere else on the internet)
4. Wash it with washing up liquid/fairy liquid/dish cleaning detergent.
I was nervous about it initially but then I figured you use it for glasses/cutlery and crockery which you then consume food from and it's okay, so why not this? I did give it a good rinse after though to make sure there were no remains of dish soap on it.
Most importantly it got rid of that bloody smell!!!