Hi Freakout
You've just 'freaked me out' with the thought of that - stifling cries, so as not to scare others.
I'm sure the designers of these 'open plan' dental offices would argue that it's not an issue because the procedure shouldn't be painful...but Lets is so right, what about privacy?
All 4 UK practices I have ever gone to, have had good privacy...in Holland the awful first one, had the Admin Assistant sitting in the surgery as well as the dentist and the nurse...you feel like you're addressing an audience or something

...
The one my Children now go to has impeccable privacy

, and the new one my husband and I now go to in Holland, is somewhere inbetween in that there is a communicating door between the two treatment rooms and sound could come through; but probably not usually an issue as it's one dentist and one hygienist and seems to have a tranquil feel to it.
I suppose if a child got very upset, they could turn the music up! I think hearing this would only upset me as the patient next door if I could not hear adequate reassurance being given...no I'll be honest, it would upset me, especially if it were an adult..so I'm sure the patient next door is very grateful to you for keeping quiet!
Are crowns really so uncomfortable?, that's the one thing I've never had....
I can see why it makes it hard for you to communicate in that open plan situation - is it always the norm in the US or just the current trend?
One Dutch practice I considered trying from the internet, turned out to have a window to the treatment room that people walking past on the street could easily look in through ...so that idea also did not appeal!
Best wishes
Brit