We have a 9 year old female Chihuahua named Mazzy.
Other than a mild case of the beetus, she's perfectly healthy. We keep her diabetes managed well and she's still active...we went for a walk yesterday, played with her toy, etc.
After she chewed through an electrical cord as a pup, she's been very good about only chewing things that belong to her....i.e., toys.
As she matured, instead of ripping toys up, if she really liked a toy, she'd take care of it and keep it for a long time.
My mother has a dog and she'd bought a chew toy for it...fabric stuffed with that fiberfill stuff. Mazzy loved it so much that she slept with it in her bed for a few days. Even after a couple of months, she still hasn't completely destroyed it and will still bring it to us to throw.
But, with that toy, she began a strange behavior. She nibbles with her front teeth on it.
And then, she started this behavior with things that she identifies as "hers"...her blanket, etc.
She doesn't destroy them. Just nibbles at them.
We gave her an old towel (being Mountaineers, it's a Gold Rush towel, lol). Right now, she's going to town on it.
Anybody ever hear of an old dog picking up a weird habit like this? I don't think there's any harm in it, as she wouldn't chew anything that she knew she shouldn't, but it struck me as odd.