Periodontal disease is a later stages of gum disease. This happens when bacterial infection, under the gums, progresses deeper and affects the bone and tissue supporting the tooth adversely. 

Gums will Bleed when brushing or flossing.Will be red, swollen and tender.

The gums will have pulled away appearance from the tooth, this is called ‘Pocket’

Pus may be seen in the pockets around the tooth.

The infection damages the bone that holds the roots of the teeth.

Periodontal disease cannot be reversed but can be slowed down by regular visits to the dentist, periodontist, or dental hygienist and also by improving oral hygiene at home.