Our mouths are full of bacteria. These bacteria, along with mucus and other particles, constantly form a sticky, colorless "plaque" on teeth. Brushing and flossing help get rid of plaque. Plaque that is not removed can harden and form "tartar" that brushing doesn't clean. Only a professional cleaning by a dentist or dental hygienist can remove tartar.
Gingivitis: The longer plaque and tartar are on teeth, the more harmful they become. The bacteria cause inflammation of the gums that is called "gingivitis." In gingivitis, the gums become red, swollen and can bleed easily. Gingivitis is a mild form of gum disease that can usually be reversed with daily brushing and flossing, and regular cleaning by a dentist or dental hygienist. This form of gum disease does not include any loss of bone and tissue that hold teeth in place.
Periodontitis: When gingivitis is not treated, it can advance to "periodontitis" (which means "inflammation around the tooth.") In periodontitis, gums pull away from the teeth and form spaces (called "pockets") that become infected. The body's immune system fights the bacteria as the plaque spreads and grows below the gum line. Bacterial toxins and the body's natural response to infection start to break down the bone and connective tissue that hold teeth in place. If not treated, the bones, gums, and tissue that support the teeth are destroyed. The teeth may eventually become loose and have to be removed.
Source: National Institute of Dental and Craniofacial Research
