Dyspraxic DS1 (19) not cleaning teeth

[Hereshoping1]

To cut a long story short - DS1 has left home, working, doing ok, I think. He is Dyspraxic - untidy, poor concentration, but sociable pleasant lots of friends etc. Except we met up yesterday and his teeth were quite frankly disgusting. When a younger teenager dental hygiene wasn't his priority but with some nagging he has escaped without any fillings. I of course tried to talk to him about it but he simply told me to mind my own business.
Any suggestions - I can't bear the thought of him having all the complications associated with gum disease and I feel like a completely terrible parent that he has got into this state.

I have trouble getting my teenagers to clean their teeth properly - won't go into their health issues

I found taking a picture on my iPhone worked a treat. Can zoom in and point out the missed bits and red inflamed gums. Not my fault! Shows up as definite evidence they need to brush more and can see another pic as evidence of improvement. Worked for me.

Does he simply forget or is he deliberately not doing it? If it's primarily forgetfulness, can he put up a check-list of things to do in the morning in the bathroom to remind him? Or put a buzzer alarm on his watch/phone?

These are the things I do with my younger DS. I do realise it is harder to police with an older child who lives away from home.

I have also resorted to buying disposable toothbrushes, which I keep in the car. Obviously they are not as good as brushing your teeth, but I'm sure they are better than nothing and reduce bad breath. A small pack of 3 takes up practically no room at all. Perhaps your DS could carry some around with him for the times when he's forgotten at home?