What are the white blotches I usually have on my teeth? And how do I get rid of !

What are the white blotches I usually have on my teeth? And how do I get rid of them?

I usually have these white blotches on my teeth. Usually on the front teeth. They aren't always there, and some days they are more extreme than others. I've noticed that it sometimes varies from day to night.

2 months ago
I did have braces, years ago, but these blotches have been there since I got my permanent teeth.
I do sleep with my mouth open, and would like to change that - how can I control what seems to be habit for me?

I have dealt with this same problem, the white blotches were really noticable in the morning upon awakening and tended to lighten up or completely disappear as the day went on. I went to my local dentist and this is what he told me:

It sounds like you're sleeping with your mouth open.Maybe you're congested and can't breath through your nose,or have allergies etc. What's happening is you're mouth breathing and dessicating (drying out) the front teeth. As the day goes on ,the enamel loses it's frosty appearence when the teeth get fully hydrated again. Treatment of choice is no treatment of all.

Hope this helps, it's nothing to worry about :)