Wrong implant - silicone instead of saline. How do I question the doctor on this?

How do I handle talking with my Dr about the fact that we had discussed my ONLY wanting Saline implants with my Breast Reconstruction? I found out today that my implants are in fact Silicone implants and about 150cc bigger than I told her I wanted. We discussed size and type multiple times and I was always clear on the size I wanted and that I wanted them to be Saline. I am a full size bigger than we agreed on and they are Silicone. How do I successfully question the dr on this?