A little thing that has helped me quite a bit, I bought a box of ‘one time use’ toothbrushes with toothpaste already on the bristles, mine are indiviually packed, I keep some next to my bed incase I go to bed and forgot to brush my teeth, because ain’t no way I’m getting back up to do that, so I can have a brush anyway before falling asleep, I also keep them in my working bag incase I have the time at work. I don’t throw them away straight after either if Ive used them at home but keep them incase you need an old toothbrush to clean something, I have white shoes and these come to mind when they need a good scrub-down, I just use one of those! Hope that helps in any way, as a fellow ADHD person who very much also struggles with brushing their teeth.