https://www.newscientist.com/article/2191842-gum-disease-may-be-the-cause-of-alzheimers-heres-how-to-avoid-it/
I can say that my gum health has increased dramatically with daily use of my water flosser:
https://smile.amazon.com/Waterpik-WP-100W-White-Ultra-Flosser/dp/B00CU9VF2Q