J.C.
You're fine to breastfeed. I had dental x-rays done when I was pregnant! I had to have a root canal and a crown put on all while I was pregnant and my Dr. said that was fine. From what I heard- the amount of radiation you're exposed to from those type of x-rays is the same amount you get from being outside in the sun. Just as a precaution they did put 3 of the metal capes on me when they took the x-rays because they knew I was nervous about it!