Periodontal disease is a condition that occurs when the tissue around the teeth becomes inflamed due to bacterial infection. In time, the inflammation and infection can lead to tissue, and sometimes bone, breakdown around the tooth in addition to conditions known as periodontitis and gingivitis. There are a number of bacteria that can lead to periodontal disease, and in many cases multiple bacteria at one time are present in the tissues. In most cases, the bacteria accumulate as a result of age and poor dental care.
Cats do not develop the same type of cavities that people get. Cats do get holes in their teeth, but they are generally the same color as the tooth and are the result of tooth resorption rather than decay.