A big part of the reason why so many people fail to take gum disease seriously is because we were just never told to do so. In order to know how to prevent periodontal disease, we first must understand what causes it. Simply stated, periodontal disease is caused by harmful bacteria living in your mouth. So, if you want to avoid the nasty consequences of periodontal disease, you must keep the bacteria at bay while taking care to remove all plaque with good oral hygiene. Using a mouthwash is an excellent way to combat the harmful bacteria in your mouth. Just be sure that it has all natural ingredients because mouth washes that use alcohol to kill the bacteria will dry your mouth out.