I have to wear them only at night.

Well, like I said, it's only 24/7 for the first month after my braces were taken off, and then I switch to only nights. But it's not going to be a very fun month so far as food goes... >>

I had to wear them 24/7 for about 3 months.

Ugh.

Appendices is correct, but not sure about the others. I'm often tempted to say "prefices" rather than "prefixes," but I don't think that's correct.

Thing is, though, apparently the dictionaries have accepted "indexes" because so many people use it.

Ah yes, the infamous retainer.

I had to wear them 24/7 after I had my expander and headgear removed when I was in elementary school. I didn't really mind wearing them, but the taste got a little annoying after a while. >>

-Niki

It ought to be "indices", really, but the correct English forms are "indexes" and "prefixes"... Don't ask me why they're like that when it's "appendices", because I don't know...

Anyway, retainer – better than braces, but still annoying. Your hygiene is admirable; when I had mine all the time I would just pop it out, eat something, then pop it back in, even if it was just a snack. It does require you to carry around the case at all times, though...