To take DS to the GP

[plodon]

Over the past week he has started sticking has bottom jaw out (Jimmy Hill style). He said he doesn’t know why he’s doing it. I’ve been watching and it is pretty much constant. Any ideas?

I have bruxism, I clench my jaw and grind my teeth sometimes too. Mines anxiety related, could it be that? It's nothing serious if so but normally the underlying cause needs addressing before it gets too noticeable.
Is he stressed or anything?

It sounds like a tic, if it is the general advice is to ignore and hopefully he will stop. How old is he and is he stressed?

He is 10 and I think he’s quite anxious at the moment.

your dentist may be better place to visit for a check up (in case he is clenching his jaws)