Welcome to the site, Lily! I'll certainly be interested in following your progress, since I'm scheduled to get my braces 1 day before you! Sorry you're in some discomfort currently, but I'm sure you've found out from reading the posts that MANY of the posters here have spacers now or have had them in the past. I haven't had them myself, but the consensus seems to be that they're more uncomfortable than the braces will be! Plus, take heart that they won't be in your mouth much longer!
I think it's natural to feel some anxiety about being braced. Compared to a lot of other health care procedures, though, there really isn't too much of a downside to straightening your teeth. I asked my own ortho about root resorption, or shortening of the tooth root, and that does happen in a few instances (about 5% of folks, is the percentage he quoted me). I certainly feel that the upside far outweighs this slight risk -- you have much healthier teeth, less prone to cavities in the future because they're easier to clean, and less prone to wear. If your teeth need orthodontal work and you DON'T have it done the ultimate risk to your teeth is far greater, IMHO!
How will people react? Well, obviously that depends on the person, but adults in braces are more common than ever these days, and almost to a person our posters here say that most people don't give a thought! Oh, they'll probably be a topic of conversation at first, because you'll look different than before. But after that who's going to care? I'm sure your husband will feel that way, too -- in fact he's probably proud of you for taking this step to improve your smile and your overall health! Try and continue to take a lighthearted approach and feel good about yourself that you're doing something great for YOU!!
Best of luck to you next Friday!
