We have a 3yr old (approx) Pit mix that we adopted 14months ago. We've crated him since the day we brought him home and still do any time we leave the house. He too is a power chewer and would find something to eat out of boredom. When we crate him we give him a frozen PB kong (the black strong chewer version) and a nylabone or other tough plastic toy.
With this pup and our prior dog (an purebred English Springer Spaniel) we found it helpful to use a "bark" collar to correct unwanted behavior. The collar can emit a tone or a small static shock. Since the tone is identical to the one that the invisible fence makes, and doggos both learned how not to cross the fence line when they hear that tone, we have had success with the bark collar only being on tone mode and NEVER on shock mode. It has a remote so any time dog is chewing something he shouldn't we hit the tone button and he immediately stops doing it. This also works for when he takes a stuffed animal or shoe or other item he shouldn't have, he will immediately drop it when he hears the tone. A few corrections of the same behavior with an item and he doesn't do it again. When our last dog would get a bit crazy every once and a while we'd only need to pull out the collar and show it too him and he'd immediately chill out...it was like warning a child they were about to get sent to time out. I know not everyone would agree with that type of collar but we've had success and feel confident using it without the static correction mode.
Mom to two amazing DDs ('07 & '09) and a fur baby.
Gluten free since Nov '11 after non-celiac gluten sensitive diagnosis. Have had great improvement or total elimination of: migraines, bloating/distention, heartburn, cystic acne, canker sores, bleeding gums, eczema on elbows, dry skin and scalp, muscle cramps, PMS, hair loss, heart palpitations, fatigue. I'm amazed.