Thanks for all the advice everyone.
Heather, I'm with you. He only uses it in the crib and he has been such a good sleeper since he was a baby, I feel so bad taking it away and making him cry. He doesn't wake up at night and ask for it except on the odd occasion. It just seems like such a simple thing for a little comfort in the crib. It's the dentist that wants it gone - I guess his front teeth are starting to buck out a bit. You know, I needed braces and my kids probably will too so I'm thinking is it really that big a deal?
Ok - I'm just making excuses aren't I? I hate messing with their sleep, even if for a couple days. I'm a wuss.
My oldest was a terrible sleeper from the get go and I threw that darn pacifier away at around 6 months of age because he'd cry every time the darn thing fell out of his mouth.
Let us know what you end up doing! 
Of course, we did get a lot of comments from people asking what was wrong with his hand because of the colored bracelets that you use to fasten it on. I will say that you have to stick it out the whole month, even if it seems like it works after just two weeks because we quit and then had to start again because the thumb started going back in his mouth. They do have a version for finger-suckers too.
