Right now, there are colonies of microbes living in your mouth. They are on your gums, tongue and lips. Most importantly, they are on your teeth. If you do not take the right steps to deal with them, they can create cavities in your teeth. Having microbes in your mouth is entirely normal and they will continue to live there no matter how often your brush your teeth.
Not all of the microbes in your mouth are harmful, most are harmless and some are actually beneficial to you. The microbes in your mouth will change from time to time based on a number of factors including who you kiss. Consider the fact that, couples who live together often have the same microbes.