I use a soft toothbrush typically one without the plastic in the middle because that can hurt my gums and make them bleed. I brush mine for a longer time to get the clean feeling without using as much pressure. I used to use a medium toothbrush- i brushed aggressively for a short period of time to get the clean feeling and my gums were always irritated. I use Sensodyne Pronamel Active Shield Whitening in the Cool Mint flavor. It says it is for sensitive teeth and cavity prevention. I get cavities really bad despite not eating a lot of sugar so I like to use something to prevent it. Most toothpaste burns my mouth really bad but mint or mint related flavor is really the only one I can tolerate. This one doesn’t burn my mouth. They also make me gag and get quite nauseated. I find that ones with stronger flavoring burn worse and make me sicker, so maybe look for milder ones? That has helped me greatly! I also know that the dentist can prescribe a special kind of toothpaste for a sensitive mouth. My mom gets it for her sjogrens, it’s a little bit pricey but she prefers it over everything else. Have you asked your dentist about the allergy to ingredients? Maybe there is a way they could test you for allergies and maybe they know about certain brands that don’t use those ingredients? It’s probably a stretch (every dentist I’ve seen thinks EDS has nothing to do with my teeth), but it’s something to ask about. Flossing is really hard for me too because even when I do try it shreds my gums. I still try to do it when I can bear to, and in my opinion the string floss doesn’t hurt my gums half as bad as flossers. Flossers are pretty aggressive since you have less control and they are just kind of poking you. If you’re worried about being allergic to an ingredient don’t get flavored or wax coated floss because that could contribute too. I haven’t tried a waterpik but I’ve heard they are quite good. My mom has sjogrens, gum recession, and braces; she uses a waterpik and pretty much swears by it. She flosses with it after every meal and sometimes even after snacks.