When the person claimed they listened to music, I can't imagine that it was with using headphones. Most dentists have music piped into their offices, usually tuned to a local radio station, as mine does. Listening can be somewhat difficult though with the noise from drills, cleaning tools, etc.
True story - this past December I was at the dentist getting some cavities filled. I obviously couldn't talk with all the crap and whatnot in my mouth. My dentist and her assistant were unusually chatty, talking about everything from softball games to how to cook cauliflower. Since it was December, Christmas music was playing over the radio. The song Christmas Wrapping started playing and they began discussing who sang it. Their consensus was that it was The Go-Go's. I immediately protested with an "Uh uh" since I knew it was The Waitresses, which I told them once they were finished working on me.