Re: use of "packing cord" for crowns?
All of my crowns were fitted, with packing cord, except for one, where the dentist cauterized the area. That actually caused more residual pain, than the packing ever did. I never had any lasting discomfort from packing cord. I'd question how well the impressions, for your crowns, are being made. Just a millimeter off, can reck how a crown fits. It's possible your tooth needs a root canal. I've had lasting pain, after a permanent crown has been put on. I end up getting the root canal, and then, after I heal from that, the tooth is alot better. I'd prefer to have no margins with my crowns, because over time, your gums will inevitably recede around the crown, creating more than enough space between the gum edge and the crown. See another dentist, if you can't talk easily to this one. I'm a big believer in second and even third opinions.