Welcome to the site.
Well, it seems like you are suffering from neuralgia that is pain along the path of a nerve which in your case has started owing to your crown pathology.
So, for your severe pain you may ask your doctor to use a combination of Pregabalin at dose of 75-150 mg/ day) or Gabapentin ( NEURONTIN) at dose of 300 mg / day and an NSAID such as Ibuprofen.
The former mentioned drug ( pregabalin or gabapentin) is well suited for relieving neuropathic pain similar to what you are experiencing while ibuprofen will act as an adjuvant/assisting drug to it.
Kindly discuss this option with your doctor and try it.
Hopefully this will mitigate your pain soon enough.
I wish you a speedy recovery.
I hope this helps.