Confusing thing-logic
Okay, some queries.
The thing can't immitate non-organic material, hence why it pushes out the metal wrist support, or spits out the tooth fillings. Does that mean the wrist becomes broken again, or does the Thing heal/repair the bones? What about the teeth? Wouldn't there be big gaps holes, and the nerves become very sensitive?
If someone had a heart-pacer, then the person-thing would have heart-problems.
At the end, she tells him he was wearing ear-rings. He feels his right-ear, but she says it was on his left-ear. the thing is meant to know the persons memories, knowledge, etc... so how could he not know which ear he has his ear ring on?