Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Gum (Periodontal) Disease ?
    ### Response:
    An Infection of the Gums and Surrounding Tissues Gum (periodontal) disease is an infection of the gums and surrounding tissues that hold teeth in place. The two forms of gum disease are gingivitis, a mild form that is reversible with good oral hygiene, and periodontitis, a more severe form that can damage the soft tissues and bone that support teeth.
    