All my top teeth have had crowns on from an early age, I recently had them replaced with all porcelain crowns but some of the tooth stumps i have are dark and unfortunately this darkness showed up through the crowns. I then had these removed and my dentist suggested metal porcelain bonded crowns instead, I have had these fitted but they don’t look right, the colour of them changes quite dramatically in different lights and they look dull, lifeless and ugly. They also seem bulkier than the previous crowns. There is a translucent area that has been incorporated into the crown which as I understood was supposed to make them more aesthetic but it doesn’t look very well blended with the crown and gives the appearance of a grey outline around the sides and bottom of the crown. I realise that metal bonded porcelain crowns are not as realistic as all porcelain crowns but mine look very false. Can metal bonded porcelain ever look natural and is this my only option due to the dark tooth stumps that I have?

Many thanks for any advice you can give me.