If anybody has ever told you that you have a filthy mouth, then technically they are telling the truth. They might not be aware of this fact. Of course, they are referring to something you have said, usually foul language. But that is not the reason as to why you do indeed have a filthy mouth.
Instead, the fact that we have a filthy mouth, which correlates to you having such a dirty and unhygienic mouth, is due to the number of bacteria present inside. We are talking about billions of bacteria inside. But that does not have to mean that every single bacterium is bad, as that is certainly not the case. Actually, we all have more bacteria in our mouth than the number of people alive in the world today, and when you consider that this is billions of people, it does make you think about how packed our mouths are.
Now, you don’t have to stress or worry about this, or go and wash your teeth out, because it’s not going to do you any harm, but the next time somebody tells you that you have a filthy mouth, hit them with this fact, as it will stop them in their tracks.