400cc Silicone Implant Under the Muscle,110lbs, 5'3, 23yrs Old, B Cup,Will It Look Bad?i

On the east coast 400 is large and most women choose something smaller but also are very interested in a more natural look, if you are ok with bulging at the top of your breast you will be fine

Without photos or measurements it is difficult to suggest a size for you. But if your surgeon felt that 380 cc was appropriate to your chest and breast anatomy, then you should be confident in that advice. In general, I find that implant sizers look larger than the same size when implanted in the breast, usually by about 10%, but this is not an exact science. In general, a 400cc implant will increase your cup size two full cups. So if you want to be a full D cup size, then your surgeons advice is sound. A difference of 20cc is unlikely to make a difference in the final result. Computer imaging is a better way to estimate the implant size before surgery. Good luck.

Knowing that everyone's body is different, try to keep in mind that your results will be within a range and not exact.  Try to go in knowing that you may be on the larger end of a C cup or on the  smaller end of a C cup and convey which range you would be comfortable with to your surgeon.  With that said, going from a 380cc implant to a 400cc implant is not going to be a very noticeable difference and not really worth losing sleep over.  Sounds like you are concerned about being too small so going with a 400cc implant will alleviate that concern because you chose the larger of the two implants.  Remember, your surgeon wants you to be happy, so you can always go see him/her again to go over expectations.  Best of luck!