Had permanent crown sealed with temporary cement removed for root canal retreatment. crown was resealed again with temporary cement. occlusion feels different. is this due to two layers of temporary cement?

Dental occlusion should be tested prior to reseating a permanent crown, and appropriate adjustments applied to remedy the seating of the crown. This is not usually due to the cement utilized.

Temporary cement is a different thickness than a permanent cement and the build up of the temp. could cause a slightly higher occlusion. This is normal but when the crown recemented with a permanent cement the bite will be checked to make sure it is even.

I'm sure your Dentist cleaned out any residual temporary cement before recementing the crown. It's possible that the temporary crown is positioned slightly differently the second time than the first time. See your Dentist. The temporary may require a simple occlusal adjustment.