Faline was a feral and is still very nervous, so she certainly wouldn't let me put something on her gums, it's hard enough getting most of her liquid antibiotic down her! Anyway, I bought the Plaque Off and will start it tonight since I just have to add it to their water bowls. I don't know how I'm going to know if it works. Dallas and Thumper were checked out by my vet tonight and he said their gums were in pretty good shape at present. Plaque Off contains anthium dioxide as the tartar/plaque control ingredient. According to a quick google search, this is an oxygenating agent that dissolves food films. It's available for human use and is used in water treatment facilities. I bought the economy size, 16oz for about $12.