Our son does it in his sleep. You can go to a Wal Mart or if you have them, a Dollar General and get a device that goes in the mouth for about $3.oo designed to keep from grinding teeth. If you can't find it, another item you can get but, it's bulkier is a mouth guard used in football. You'll need to cut off the thing that attaches it to the helmit.

Our dentist made a mouth guard for my son and we made him wear it every time he would grind and click his teeth (beat giving him sugary gum!) and he soon stopped because he didn't like to wear the mouth guard. We also bought a chewy stick from one of the special needs companies and a chewal necklace for him. This helped too.

My son grinds his teeth on and off. I think it has something to do with the sensation & feeling for our son. He does it realllyy hard sometimes, even chipping some teeth..

Will used to do that too. All I could really do was to use my stern voice telling him to stop. He did it for over a year and I feeling he probably stopped because he wanted to, not from me telling him not to.

Iknow this is an old question...My son does this too, at first I and everyone thought it was just a "stim"...but it is actually what he does when his stomach hurts, after taking our allergens from his diet and getting on miralax he rarely does it (and when he does and you ask him if his stomach hurts, which he can now answer he always says yes)