Can a front tooth permanent cemented crown that does not match other natural teeth be made a shade darker without sending it to a lab? too intensive.

Unfortunately not: There is no way I know of to change the shade of a porcelain crown that is in a patient's mouth. It may be easier to have whitening done on your natural teeth to make them match the crown then to have the crown redone.

Sorry, no: The permanently cemented crown will need to be removed (destroyed) and a new crown will need to be fabricated.

Wrong shade: Any tooth that is permanently cemented can not have its shade changed without first taking it off and if it is permanently cemented, trying to take it off will most likely either break the crown or damage the tooth. If the crown was intact, it has to be baked in a ceramic oven to change the shade and very few dentist have an on site lab/technician to do that. Sorry, there is no easy solution.

Afraid not: The color of a permanent crown is baked in when it is fabricated, so color change usually means removal/replacement. Your Dentist can, however, fabricate a temporary crown for you to wear as the new permanent crown is being fabricated. That way the transition can appear seamless.