Thanks for continued input. I am going to write the letter - in fact DH already wrote a draft but I wanted to tweak it. But for some reason I seem to be avoiding it, I'm still upset about it.
This was not the holistic dentist, Xantho. We saw the holistic dentist and he successfully filled one of DD's cavities (an urgent, deep one). The holistic dentist, who I still like and respect and may see again for ME, apparently does not that well with kids. We were honestly a little upset after we left, but that was nothing compared to this week's visit. The holistic dentist said some things that were really not cool at all, including telling DD she was being a "bad girl" at one point when she was crying (crying, but not preventing treatment). Yet he still treated her like a person, talked to her, at least tried to help her through the process, said mostly kind things, etc. We decided to take her to the pediatric dentist instead of returning to the holistic one given that it wasn't a great experience (though not an utter disaster, by comparison). The pedi dentist treated DD like an object, and specifically an object that was interfering with his day. He did that from the very beginning. Ah, here I go recounting it all again, sorry guys, I tend to do that.
I think we will do the letter and just go from there. While I'm not counting on it, I think there's a reasonable (though small) chance we just might never hear from them again and that will be that.
One thing that is on our side is that we were referred to this pedi dentist by a regular dentist. (Sorry, I know, we've seen so many). I called the regular dentist's office yesterday and explained the situation. The receptionist I talked to was upset to hear it, and when she called back she said the dentist was upset too. This dentist is extraordinary in his customer service skills, so this would actually and truly concern him. Not to be confusing, but he referred us to to a specific pedi dentist, who owns the practice. He said specifically that it had to be HER. I got the message, and made sure to communicate that. We got an initial visit with her, and she set up a treatment plan. Then we made the first treatment appointment, and I was surprised to see that we didn't get her (though her name is on the appointment card I have), we got what turned out to be her part time associate.
So I'm sure SHE is a good pedi dentist, and I think there is a really good chance our regular dentist will call her up and discuss it. I'm also sure that whatever is said will gloss things over (since neither dentist was there and she'll have the story from her associate's point of view) but at the same time, our regular dentist has an upset patient, and he's a colleague and major referrer of hers. Even if she believes her associate and thinks we're nutcases, there is a bit of pressure here for her to just back off, I think. Since the regular dentist was careful to say it had to be HER I am thinking there have been complaints in the past about the associate. And that's a big deal. Since the regular dentist is so huge on customer service, he may honestly have to think twice about referring anyone to the pedi dentist again, even if she is that terrific, since she apparently has a major liability on her staff.