Poor Oral Hygiene Plaque remaining on the teeth can lead to periodontal infections.   Smoking and Use of Tobacco Raise your chances of getting severe forms of the disease and may limit success of treatment.   Pregnancy Changes in hormone levels may make the gums more sensitive to plaque.   Stress Makes it hard for the body to fight off infection.   Medications Some drugs, such as birth control pills, antidepressants, heart medicines, seizure medicines, and cancer drugs may affect your gums.   Clenching or grinding your teeth Puts extra force on the supporting tissues and could speed up the disease.   Diseases Some diseases like diabetes and AIDS make you more prone to infection and may make periodontal diseases more severe.   Poor Diet Can make it harder for the body to fight infection.   Bridges that no longer fit Raise the chances of retaining plaque.