Can 450cc silicone implants make a B cup to a D cup?

While it's good I think to have a general idea of what implant size you can expect to end up with to achieve the results you want, I think it's more important to have good communication with your surgeon so that he or she knows exactly what your goals are. This communication will allow him to make the best judgements at the time of surgery to give you the final result you want, and in your case, that may involve an implant that ends up being a bit smaller or a bit larger. In the end, it's not the implant size you end up with, but the breast size, shape, and balance with the rest of your body that really matters.
Good luck!
Dr. Salemy

It is unfortunate that we don't have a better system than cup size because it is so innaccurate. Trying on implant "sizers" in a D-cup bra or the rice bag trick mentioned below are good ways to start, but decifde if it looks proportionate on your body without thinking about the cup size per se.

It is important not to focus on absolute cup size when inquiring about breast implants. The most important thing to determine is what looks best for you. A 450cc implant will look different on a person with a narrow frame versus a wide frame. The best idea is to have your plastic surgeon let you feel a sample 450cc implant, look at it when placed over your breast, and decide if it will give you the look you want. Good luck.
Dr. Cuber