Will a 325cc be big enough for a small frame? I"m 5'5", 115lbs, small frame.

You will answer that question yourself if you have had an
opportunity to try on different implants in a bra during a consultation. If
your doctor has recommended 325cc and you have seen what that looks like and
are happy with it you are all set. I hope that you tried on implants that we're
both smaller and bigger than that to know what your ultimate result will look
like.

It is common for patients to be concerned over selecting a larger implant than expected, and post-operatively, the same patients become concerned of not selecting a more larger implant. As such, it is important to select implant size based on the patient's breast characteristics so there is no debate over what is too much, or too little.Please know that it is a common misconception that implant size correlates
with the bra cup size. A bra-cup size itself requires many measurements to
describe it.
Bra sizes vary among manufacturers, and they can label the cup size by any
designation they choose. So a C will be a D for another. Additional factors, such as demi and full
cup coverage, specific fabrics, padding, and elastics, can all affect the fit
of a bra.
If we consider all things being
equal – i.e., you get a bra from the same manufacturer and of the same style, -
then I think you might find it helpful to know that a study by Dr. Bengtson and
Dr. Glicksman titled “Standardization of Bra Cup Measurements” has shown that
the average implant volume required to increase the cup-size by 1 size is equal
to 205 ccs. It was also found that normally breast augmentation increases the
cup size by 2. However, it is also important to consider the profile as even a
smaller implant with a high profile can increase cup-sizes by the same amount.
Now, it may be helpful to do
bra-sizing trials with the bra of your choice when you go in for a
pre-operative consultation with your board-certified plastic surgeon. Now,
although you give importance to
cup size designation, what should matter most is that the implant looks good
aesthetically and that the chosen bra fits and feels comfortable. I believe you
recognize this as you mentioned you want the implant to look proportional to
your body.
Once again, the implant has
to fit YOUR body dimensions. The more you deviate from the proper fit,
the more fake your breasts will look.
Surgeons use what is called
tissue-based planning. The planning takes into account the effects of implants on tissues over time,
risks of excessive stretch, excessive thinning, visible or palpable implant
edges, visible traction rippling, ptosis (Sagging), and breast tissue wasting.
To determine the final implant size, breast measurements
need to be made:  base-width, breast skin
stretch and nipple-to-Inframammary fold distance. The combination of these
measurements along with your preferences will help determine tissue coverage and the required implant
volume to optimally fill the breasts.
So please focus more on having full and natural
looking breasts rather than trying to fit into a particular bra-cup size.  
All
this being said, share all your motivations for surgery, expectations
and goals with complete honesty to avoid miscommunication and post-operative
concerns/regrets. Be as specific as you can about what you like regarding your
breasts and what you don’t like. If you trust your surgeon and their judgment and the
decision-making method used to choose the implant size, then you should be in
good hands.
Hope this helps.