Periodontal (gum) diseases, including gingivitis and periodontitis, are serious infections that, left untreated, can lead to tooth loss. The word periodontal literally means "around the tooth." Periodontal disease is a chronic bacterial infection that affects the gums and bone supporting the teeth.

Periodontal diseases are infections that affect the tissues and bone that support teeth. As the tissue are damaged, the sulcus develops into a pocket that is greater than three millimeters. Generally, the more severe the disease, the greater the pocket depth and bone loss. The enlarged pokets allow harmful bacteria to grow and make it difficult to practice effective oral hygiene. Left untreated, periodontal diseases may eventually lead to tooth loss.