My 6 year old daughter does this. I did check with the dentist when I initially took her in at her 3 year old check up and he said it is quite common and harmless. It's very annoying to the people who have to listen to it but he said a mouth piece at this young age is not necessary and not really the safest course of action. He said she'll probably grow out of it, most children do. But I clench my teeth in my sleep and have tmj so I have had to be fitted for a mouth piece.
I'm 27 and my fitted mouth piece comes out of my mouth sometimes when I sleep. Sometimes in the morning I wake up and it's just free in my mouth, or sometimes it's lost somewhere in the bed. Because of this there is no way I would put something like that in my child's mouth...too much risk for choking.
at 6:18 AM on Feb. 23, 2009