Periodontal disease is mainly caused by dental plaque and the bacteria that forms it. These bacteria form a sticky film that constantly coat your teeth; and if not properly removed by thorough brushing and flossing, can harden into rough calculus or tartar. The bacteria found in plaque produce toxins or poisons that can irritate the gums and cause them to bleed, swell, and turn red. If not properly cared for, the gums will remain irritated and they will begin to separate from the teeth and form pockets. When left untreated, the disease advances which causes bone and supporting tissues to break down and may lead to tooth loss and severe recession.