Hello ,
Thanks for writing to us,
I will be glad to answer your query.

First of all, thank you for sharing your pictures with us,
After carefully examining the pictures and reading through your query I would like you to know that there is nothing wrong with your tooth.
It seems perfectly healthy.
In fact, sometimes sudden trauma to the tooth can cause temporary inflammation of the surrounding tissues, but in your case I could not see any such changes, therefore you need not worry.
But if you feel pain or swelling, then warm saline rinses can be performed (3-4 times/day) to relieve symptoms.
The trauma from the metal chain was not at all hard to affect the tooth or its tissues.

I hope this answer was useful.

If you have any further queries feel free to write back to us.
I wish you good health.
Take care.

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