Wording an email to abusive ex

[Nchanged89]

Hi, I need to email my clown of an ex. DD is 16, needs braces, all approved by orthodontist but she needs to see hygienist at her dentist before we see orthodontist again.
Ex dealt with all dental stuff before, he's passed the orthodontist on to me and is seeming he wants to pass the dentist on to me. He is a bare minimum dad, doesn't pay a penny over his CMS, won't do anything extra. I have no contact with him as he was/is abusive. I have a separate email address that I use for contact with him when it's essential. I basically need to tell him to stick it up his arse, I will take her to orthodontist but general dentist appointment, were and should still be his responsibility as he registered her, takes her and deals with it.
Can anyone help me word this, he is a nasty abusive individual, no matter what issues I've raised in the past, he turns it round to be all my fault with nasty insults thrown in.
The thought of contacting him makes me feel ill with anxiety.
Can anyone help me word it.
Thanks.

Not sure why she needs either parent to attend? Is it because you want him to pay for the treatment? If you can get there without driving then I assume she can too?

She's v nervous of dentists, the whole thing with her braces is quite overwhelming too with the treatment she needs before they fit the actual braces.
And big 🤣 to expecting him to pay for anything never mind dental treatment. It's all under the NHS anyway, so no its not because I expect him to be paying.

Can her brother, who is 18, take if he's available?

I used to have my older siblings take me to some medical appointments including orthodontist appointments simply because they were free and my parents were working.

If he gets wind of this he will make an excuse to why he won't have her on that day.

Why? It's no skin off his nose if she pops round the dentist for the 20 minutes it's going to take to get her teeth cleaned?

Who knows why he is like he is.
His hatred of me for finally leaving the abusive relationship and moving on with my life combined with me blocking him on everything so he couldn't continue to abuse me seems to be the main reason.