NIDCR: Periodontal (Gum) Diseases - The National Institute of Dental and Craniofacial Research describes gum disease and presents an overview of risks and treatments.MayoClinic.com: Gingivitis - Symptoms, causes, treatment, and prevention.
Gum Disease Information - The American Academy of Periodontology's description of periodontal (gum) diseases, including gingivitis and periodontitis.
ADA: Gum Disease (Periodontal Disease) - Detection, treatment and, prevention of periodontal diseases, from the American Dental Association.
MEDLINEplus Medical Encyclopedia: Gingivitis - Illustrations, causes, prevention, and treatment, from the National Library of Medicine.
