Is gum disease the same as periodontal disease?

Not exactly: Gum disease or gingivitis is the precursor to periodontal disease. Untreated/uncontrolled gingivitis can progress into more inflammation and then bone loss/recession which is periodontal disease. They are directly related but not the same. See your dentist for more info.

Yes ...: Technically speaking..Periodontal disease includes gum disease. You can have gingivitis but have no bone loss. However, the use of gum disease implies both the gums and bone are diseased.

Classifications: In the classification of periodontal diseases the most common one is gingivitis. It only affects the gums. Periodontitis affects the gum and bone. Generally we refer to all types of periodontal disease as gum disease, even if that is not technically correct.