Periodontics is the branch of dentistry dealing with diseases which affect the gums or tooth-supporting bone.

It is used to treat two diseases: gingivitis and periodontal (or gum) disease. Gingivitis afflicts the soft tissue that protects the teeth (the gums). Gum disease designates a category of infections that attack tooth-supporting bone and other tissue such as the periodontal ligament and cementum.

The leading cause of gum disease is bacteria in the mouth and gums. Too many bacteria can even injure tissue.

Certain factors can aggravate this condition, like tobacco-use and infection with diseases like diabetes.