I would definately get his teeth checked out.  Kathy who belongs to this site, had a minpin, who was a one dog wrecking crew, to put it mildly.  Anyway, after having some baby teeth pulled, the chewing stopped.  Bitter apple is a good idea also.  If you ever get an accidental taste of it, its pretty bad, and its something your minpin won't forget. 

  You also might want to go to the butchers, and get a thigh bone, or such.  Mine go gaga when they have the real thing, versus a hoof or rawhide.  Can you contain you minpin in the kitchen at night (with a bone) to lessen the chances of him chewing up your possesions?

Spinner did the same things till he was a year and a half old. He chewed the corners off all the blankets and bedspreads and tore up the carpeting (it was old no no great loss). I know your problem, he'd do it when I was in the kitchen making supper, or in the bathroom. When I'd catch him at it, I'd give him a cow's ear or rawhide chew and say "No, chew on this". They're real hyper and always have to be up to something. I'd always take a rawhide or two to bed with us at night so he wouldn't chew on the blankets. If he's crated 9 hours a day, he's got to make up for it when you're home. These are very active dogs! When Spinner was demolishing everything, we took turns watching him and always replacing what he was chewing on with cows ears or rawhide. I don't like the idea of him being muzzled all the time either and that could lead to other problems, like he could start shredding things with his nails out of frustration if he's unable to chew. I feel sorry for the dogs. They have to be so active all the time or they do resort to chewing to kind of the comfort themselves. He could have some anxiety over his first owners having him a year and then getting rid of him too. With training on what is proper to chew and someone in the household always keeping an eye on him I think you can lick this. Spinner did it till he was 18 months old. Don't give up on him.

does he have any extra teeth (like baby teeth that he hasnt lost)i own a few min pis and my mocha girl chews not as bad since i used tobasco sauce hot hot hot sauce seemed to work well

Where is he at night that he's able to destroy things? I wouldn't recommend leaving a muzzle on a dog when not supervised, it's a recipe for disaster! Have him sleep in your bedroom with the door closed, and remove anything from the floor that he can destroy, also a nice walk before bed should help.

also a nice walk before bed should help.

 

I totally agree, a tired dog, is a good dog.  Start teaching him tricks, mental stimulation can sometimes be more tiring than a good romp in the back yard

 

Have you taken him to the vet yet to have his teeth checked?