That's a really interesting question. We bounced it around in the Orthodontics Worldwide chat and of course opinions varied a bit. My own thoughts:

I don't know of another historical era that would have produced the conditions that made my "interest" come to the forefront like it did. In most times before the recent era, I'd have likely been a poor or low-class working man, without the time, energy or education to pursue something as inherently frivolous as an interest in something comparable to braces (or anything not directly contributing to my day-to-day survival). We now have the luxuries of time and leisure that didn't exist for most people in history.

Thus, I suspect that, had I been born in an earlier era, I'd have never developed an interest in many things outside my direct needs.