Periodontal disease is often silent, meaning symptoms – particularly pain – may not appear until an advanced stage of the disease. However, you should still be on the lookout for the signs and symptoms, which include:

Red, swollen or tender gums or other pain in your mouth
Bleeding while brushing, flossing, or when eating certain foods
Gums that are receding or pulling away from the teeth, causing the teeth to look longer than before
Loose or separating teeth
Pus between your gums and teeth
Sores in your mouth
Persistent bad breath
A change in the way your teeth fit together when you bite
A change in the fit of partial dentures
If you notice any of these symptoms, be sure to contact your dentist or periodontist right away!

-Perio.org