The main cause of periodontal disease is the accumulation of plaque bacteria. Plaque is an often colorless mass of bacteria that sticks to the teeth, crowns and bridges, and other tissues in the oral cavity. Plaque is constantly forming on the teeth. Plaque irritates the gums, causing them to become red, tender, and swollen. If not removed daily, plaque becomes the hard material known as tartar or calculus. Calculus cannot be removed by brushing and flossing alone. A dentist, periodontist or hygienist must remove it manually to stop the disease process. With time, the tissues that attached the gums to the teeth are destroyed by plaque and its byproducts. The gum "pull away" from the teeth and pockets begin to form between the teeth and gums. Plaque and calculus continues to fill these pockets until eventually, the jawbone supporting the teeth is destroyed. Other factors can modify how your gums react to the plaque or calculus, thereby altering your body's response to the disease and affecting your overall health: Smoking/Tobacco use Diabetes Stress Medications Clenching or Grinding Your Teeth Pregnancy and Puberty Diet and Nutrition Immunosuppression (i.e. leukemia, AIDS)