Help docs! i'm trying to find out what causes periodontal disease, and what is it?

Periodontal Disases: Poor oral hygiene. See: http://www.Mouthhealthy.Org/en/az-topics/g/gum-disease.

Multifactorial: Primary cause of periodontal disease is superinfection of specific bacteria/bacterial products due to poor oral hygiene or poor host reaction to bacteria/bacterial product. Poor occusion will cause exacerbation of the severity of the disease. Medical health condition (diabete), such as disease which compromises the immunity will contribute to the degree of destruction or the rate of destruction.