4 yo Grinding Teeth

[Guava~Lush]

It seriously wakes me up at night! Its so loud! I even stick my finger in his mouth to try to pry them apart. I know I shouldnt do that but its like nails on a chalk board to me!
What do I do? I have ground my teeth and worn them down to holes, needed caps several times and my night guard gives me headaches.
I dont want that for him, poor kiddo.
A friend said it means he has worms? I thought it was stress, it is for me. I did a search here and someone mentioned mineral deficaincy? But only 1 person replied.

Please if anyone has suggestions? And I'll stop trying to pry his mouth open, I cant really since he's asleep and they are clenched so tightly.
Thanks!!

[lovebug]

this is of the norm when kids are growing their bodys ae tring to adj to everything however if yo want to get her in to the dentist he will prob send you to and orthodontist!!!!!!!! but when i worked in pedo dental we would most of the time let the grow out of it unless the had joint probs!