Can porcelains crowns be lightened in color by lab?

Hello there,It sounds like you're unhappy with the shade of your new crowns.  Generally, the lab will remake a crown if the shape and/or shade is off.  Be sure that you're happy with the way your crowns look before having them permanently cemented.  It's always important look at before and after photos when selecting a dentist. This will give you a pretty good indication of what you can expect. Good luck and I hope this helps. Follow me if you have more questions.Sarah Thompson, DMDSt. Louis, MO area (O'Fallon, IL)Real Self 100

Hi, thanks for write... Sorry about that, but if you don't feel comfortable the better way is do a new ones, if they try to change could be worse. Regards 

While in SOME cases extrinsic stains can be polished off and give dental crowns and veneers a lighter color, the rule of thumb is to go from light to dark.  This is usually accomplished by a process of staining.