Do my temporaries (crowns) have to be the way I want them before the impressions!

Do my temporaries (crowns) have to be the way I want them before the impressions are sent to the lab?

I am having my two front crowns redone and the temporaries are not exactly the way I want my new crowns to look, example, the line down the middle not perfectly centered (stuff like that). Should I have the dentist perfect the temporaries and make a new impression before he sends it to the lab?

4 days ago
The dentist did tell me that the closest we can get the temporaries the better. He also took and impression of them to send to the lab. So that leads me to believe that they are basing the new crowns quite a bit on the temporaries.

4 days ago
I am basing this question on the shape and structure of the crowns, not the shade of them.

The lab will center the midline of the crowns on the midline of your lower, natural incisors. The temporaries are only temporary, but they should be somewhat acceptable in shape and contour--length especially. The fine tuning will be done by the lab--don't worry about that... The temporary impression to the lab will be merely a guide for the final product. The lab will use the basic dimensions of the temporaries to build the new crowns. The intricate details and other anatomic features will be totally independent of the temporaries.

If you are not absolutely, 100% happy with the result at the try-in appointment, do not accept them. Sometimes, you can wear the new crowns with a temporary cement as a trial to see how you like them. Of course, nothing will be perfect and your natural teeth are always the best as far as looks and function. Also remember that natural teeth are not perfect and any attempts to mimic absolute perfection will result in teeth that look fake. Good luck with everything!!