Periodontal diseases are often classified according to their severity. They range from mild gingivitis, to more severe periodontitis, and finally acute necrotizing ulcerative gingivitis, which can be life threatening.
Bacteria can cause inflammation of the gums.
Although bacteria are normally found in our bodies and provide protective effects most of the time, bacteria can be harmful. The mouth is a great place for bacteria to live. The warm, moist environment and constant food supply are everything bacteria need to thrive. If not for a healthy immune system, bacteria in the mouth would rapidly reproduce out of control overwhelming the body's defense system. An infection begins when the body's immune system is overwhelmed.