Sensory stuff

Really just a rant as I don't suppose anyone can help. The battle continues with teeth brushing. My son is 15 and will do whatever he can to get out of doing it. I have tried so many different things to make it better for him but this morning, I took his phone and told him he wasn't getting it back until I watched him do his teeth. The result was him screaming and slapping himself around the face repeatedly before pulling my hair. I don't want his teeth to rot and fall out after his gums get bad. I am tired. I have tried everything including


*Tooth pastes and liquids, sooo many different types and brands!
Fruit flavour
Mint flavour
No flavour

*Tooth brushes
Firm, medium, soft
Nano ultra fine
Three sided
Electric
Sonic
Musical timer

*Reward stickers

Am I missing anything? Anything else we can try?