“Leaking Crowns? All Porcelain Dental Crowns Installed on my Four Front Teeth”

Need a good lab and dentist to do this kind of work, do a lot of research ahead of time. I broke two of my teeth in a jet ski accident, and the other two were deformed from birth. They previously had overlays on them.

I recently had all procelain dental crowns installed on my four front teeth. When I floss two of them at the gumline, I can taste and smell a foul bacterial scent on the floss. The dentist poked around with a dental instrument and says they fit properly, but I disagree. None of my other teeth (crowned or real) produce the odor, so something isn't right. He told me x-rays won't necessarily show whether or not they fit, so is there a definitive way (i.e., special type of x-ray, MRI, etc.) to determine if the fit is correct?

Updated on 11 Apr 2011:
The x-ray didn't show any leakage, but it was clear to me their were two crowns that didn't fit. They have since been replaced. I found an excellent lab and my dentist agreed to use them. We split the lab fees and replaced all 4 crowns. There is no longer any bacterial leakage taste, so I'm positive I was correct. These are much thinner and I spent 6 hours on two different days at the lab. My dentist liked their work so much he now uses them for his other patients too.