Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen, red, and may bleed. In its more serious form, called periodontitis, the gums can pull away from the tooth, bone can be lost, and the teeth may loosen or fall out. Bad breath may also occur.

Periodontal disease is generally due to bacteria in the mouth infecting the tissue around the teeth. Risk factors include smoking, diabetes, family history, and certain diseases and medications. A diagnosis is made by inspecting the gum tissue around the teeth both visually and with a prob eand X-rays looking for bone loss around the teeth.

Preventing gum disease involves good oral hygiene and regular professional teeth cleaning. Recommended oral hygiene include daily brushing and flossing.

In early cases, periodontal therapy such as scaling and root planing may be recommended. In more advanced cases, periodontal surgery, or laser therapy, may be indicated.

Globally 538 million people were estimated to be affected in 2015. In the United States nearly half of those over the age of 30 are affected to some degree, and about 70% of those over 65 have the condition.