If you already had Xrays done and your dentist says the crowns are well cemented then the bad odor should not exist. I recommend mouthwash and waterpick (water floss) just after the floss, brush and mouthwash, once a day at nights. the waterfloss makes a big difference.
All porcelain crowns are bonded to your tooth using a resin cement. Once these crowns are bonded the margins should be very smooth and virtually undetectable. If you are feeling something there it may simply be excess cement that needs polishing. Hope this helps.
Short answer: yes. simply express your concern to your dentist. hopefully you could afford to chose a cosmetic dentist specially hen it is your front teeth that you are restoring.
