Brief Answer:
There is no scientific evidence to avoid or use it.

Detailed Answer:
Hello and thanks for the query.

I have read your question and understand your concerns.

There is no specific medical evidence for chewing ice by a patient with Parkinson's that may be a good or bad thing.

So, if you feel better chewing ice it is okay if you see anything wrong especially with the mastication muscles being tighter, you should avoid it.

Hope you found the answer helpful.

Let me know if I can assist you further.

Take care.

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