With the many kinds of bacteria that cause gum disease, to list them all, including their official names, in this article would quickly make it appear to be a doctoral thesis. The fact of the matter is that the human mouth contains millions of bacteria. These bacteria number over 500. If people could see the bacterium which lives inside the human mouth, under a microscope, they would more than likely be horrified. Porphyromonas gingivalis is one of the bacteria known for causing gingivitis.

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