Can you see if there is a leak or open margin of the crown through X-ray?

My porcelain crown(with metal) has been there for around 6-7 years and recently I realized that one side of the gum beside the porcelain crown hurts when I floss, and the metal part of the crown is exposed in some area. The denist office told me that they see no problem from the X-ray that I took last month. I know that you cannot see the cavity inside the crown through X-ray, but can you see if there is a leak or open margin of the crown through X-ray?