I would like to send out a message to all you thumbsuckers out there. Unfortunately most of you can't read yet. Anyway I can still remember the rage I used to feel as a pre-schooler when somebody would walk by and tell me to quit sucking my thumb or worse yet have the nerve to grab my hand and jerk my thumb out of my mouth! It made me more determined to suck away!
By the time I went into the first grade I could stick my tongue out while clenching my teeth together. A skill all my friends thought was really cool. (they didn't know I sucked my thumb because of course I didn't do it at school). Then of course my baby teeth fell out and all my permanent teeth came in beautifully. I never wore braces!
So to all you rude people stressing because your children are sucking their thumbs and trying all kinds of silly methods to stop it (like putting bad tasting stuff on the thumb - it doesn't work because the stuff sucks off in a matter of minutes!). Don't worry about it. At least if they quit before their permanent teeth come in they should be fine. Actually I sucked my thumb in my sleep until I was around 10 years old.
My mom tells me that she asked me when I turned 5 when I was going to quit sucking my thumb. I told her when I started school. She left me alone. I stopped.