Yeah. Phlox told T'Pol she had a cavity, and she insisted that was impossible since her teeth were "properly" coated with some futuristic treatment many years ago. I guess it's not supposed to wear off or last a lot longer than it did. Still, the doctor insisted and told her it would take a few seconds to correct, and bingo bingo bongo and erving, it was done. And that was 200 years before Voyager and the EMH.
I saw the other day a treatment using some mercury compound, I think, or silver compound? I forget. But it was almost as fast. One doesn't have to drill out the cavity - the solution bonds to it, kills it, fills the area. It's quick and painless and cheap, and done more and more in less developed countries. The downside? The treated areas are quite dark, maybe even black, so cosmetically it looks pretty bad - but still better than a mouthful of missing teeth, abscesses, cavities, and the ever present smell of decay and rot coming from your mouth.
I'm sorry. I just meant to say, Yeah, they did - on Enterprise, but I don't recall it happening on any other Trek series. But if it were that quick during the time of Enterprise, I can only imagine the treatments are better later on, more durable or more permanent, quicker, or maybe even they have home/quarters self-treatments that will do it with an oral rinse and give you the right color match, to boot.