So. In a way to not downplay it any, I have nearly a lifetime of horrible dental hygiene practices. Before maybe the last year or so, I only rarely brushed, almost never flossed, and only usually used listerene occasionally and I avoid dentist visits with an ardent passion like my survival somehow depended on it. My teeth have, obviously, been decaying quite a bit, but even when the decaying started, that still wasn't enough to convince me to change my ways. Around a year, maybe a year and a half ago, my gums where my teeth met would start bleeding if I did nearly anything, from spitting, to biting into soft bread, even talking in certain ways could make my gums start bleeding. At that time, thats when I realized, I REALLY needed to salvage what little bit I could. I started brushing regularly a couple times a week, which I had to do because brushing would, also, cause my gums to bleed. Over the last year, I have managed to build up to being able to brush at least twice a day, with little to no gum bleeding under almost any normal conditions at all. Until now, my brushing is always done solely with clean, fresh water, because I don't know the answer to the titular question. With teeth that at a relatively (I think) moderately high level of decay, would toothpaste and specifically a flouride-based toothpaste, be...."good" for my teeth, or with a moderately high level of decay, would it do even more damage? As a veteran, I have started planning to visit a Dental Clinic of some sort and face the music, to find out what my future options are for. Thank you for any time spent on this topic.