Thanks for putting up your question on Just Answer.
The reasons for the heat sensitivity could be because of the following problems associated with the root canal that you had:
1. Over instrumentation during the root canal ( going beyond the root canals)
2. Forceful irrigation ( injecting the irrigant solution which pushes it past the root canals)
3. Inadequate instrumentation (some amount of pulp
tissue is still left , which when touched causes pain
4. An entire root canal missed ( not picked up on an X ray)
5. A broken instrument being left inside the root canal.
Ideally root canal treatment is supposed to make the root canals sterile. Since your dentist is prescribing anitbiotics, he clearly isnt sure that the root canals of your tooth are sterile.
Sensitivity to hat generally indiactes ireversible pulpitis
. I suggest you seek a seond opinion from an experienced endodontist and get the tooth evaluated.
i dont think there is a problem with the crown.
Hope this answers your question. Feel free to contact me again for more information.
I wish you a speedy recovery !!!
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