Is good oral hygiene best known way to treat gum disease?

That and .....: Two things are essential- first, proper oral hygiene and second- proper periodontal treatment.

Prevent, not treat!: If you have a mild or simple gum inflammation, good oral hygiene will be effective. However, if your teeth is already experience moderate gum disease (periodontitis), you may need a dentist help to diagnose, treat, and maintain the healthy states. Good hygiene is a main component in all phases: disease prevention, treatment, and mainenance.

Prevention: Not to treat it, but to prevent. If you already have been told you have gum disease, you cannot treat it on your own at home.

Yes, for gingivitis!: The greatest prevalence of gum disease is gingivitis. This is an inflammation of the upper visible surfaces of the gums. It is completely reversible by daily flossing and a vibratory toothbrushing technique used at the gum-tooth interface. If you skip a single day of flossing and brushing, a new inflammatory response will occur to the new "growth" of plaque and gingivitis reoccurs.