Severe Gum Disease (IMAGE) Experimental Biology Caption The mouth of a person with severe gum disease. Bacteria involved in periodontitis have been linked with Alzheimer's disease, aspiration pneumonia, rheumatoid arthritis and other common disorders. Credit Image courtesy of Jan Potempa, University of Louisville. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.