Gum, or periodontal, disease can cause inflammation, tooth loss and bone damage. Gum disease begins with a sticky film of bacteria called plaque. Gums in the early stage of disease, or gingivitis, can bleed easily and become red and swollen. As the disease progresses to periodontitis, teeth may fall out or need to be removed. Gum disease is highly preventable and can usually be avoided by daily brushing and flossing. One indicator of gum disease is consistent bad breath or a bad taste in the mouth.