Back in the 80's I bought a weird thing that was a soft but firm rubber like material. It was about as long as a mouth guard and as big around as a pencil eraser. It had little nubbies all over on it. The idea was to put this at the gum line around the top or bottom teeth and then roll it up and down the gums to help with blood circulation. I had it for a long time and I did not go to the dentist much back then either. I can't remember who made it but it was a weird invention that never took off. Wish I still had it now. I tried using a rubber jar seal once but it never seem to have the same effect.
By the way, I've told my husband for years, "I don't get it! When I don't brush my teeth as often I get good check ups but when I brush 3x & floss 3x a day I have horrible check ups!"