Do implants appear smaller inside the body?

I would say that in general when using the mentor sizing system that the implants once placed under the muscle will appear about one size smaller (25cc, or a tablespoon) after surgery is complete.  if you are on the cusp between two sizes I would choose the larger one.  Hope that helps!

HI. This if definitely true - if you are happy with a particular size of implant in your bra then you need to have a slightly larger implant put in to achieve this volume. You need to add 25-50cc, especially if you are using shaped implants.Try to find someone with a Vectra 3D imaging machine in your area to
simulate your breast augmenation result - in a recent article (Oct 2013) of
Plastic & Reconstructive Surgery Journal (Plast. Reconstr. Surg.132:
810, 2013.), the main Plastic Surgery Journal worldwide, the 3D imaging VECTRA
machine was found to be beneficial for patients considering breast augmentation
surgery.
The article concluded that patients prefer a center that offers
three-dimensional imaging technology; they feel that the simulation is very
accurate and helps them greatly in choosing the implant; and that if they could
go back in time, they would choose the same implant again. All the best with
your decision. Regards Dr Charles Cope

   The implants will look a bit smaller, particularly in the submuscular position.  There is no rule here, but you may want to add about 10% to the size you select from the sizers.Kenneth Hughes, MDLos Angeles, CA

Sizers are not 100% accurate in depicting your final appearance in clothes. They give you a rough idea. Don't get caught up trying to decide between 25 cc differences; small volumes like this (5 teaspoons) over a breast surface area is irrelevant. It is true that most women wish they would have gone bigger, so if you are trying to decide between two sizes, I usually recommend the larger. I would say that when an implant is placed "under-the-muscle", you may see about a 10% reduction in projection related to the muscle pushing on the implant. In reality, however, every size looks different on every patient depending on a multitude of anatomic characteristics. I would also trust your plastic surgeon's advice so the results satisfy your goal cup size desires while looking beautiful and natural.

In general, implants placed behind the pectoralis muscle will appear slightly smaller than the sizer you look at in a bra or tight t-shirt. If the implant is placed behind the breast tissue but in front of the muscle, it will appear more similar in size to the sizer you try on pre-operatively.Your plastic surgeon should be certified by the American Board of Plastic Surgery and ideally
a member of the American Society for Aesthetic Plastic Surgery (ASAPS) that you
trust and are comfortable with. You should discuss your concerns with that
surgeon in person.

Robert Singer, MD FACS

La Jolla, California

I size my patients by placing in the implants in the bra and yes they do look a bit larger when they are in the bra on top of the breast. We usually recommend that the patient go up 1 implant size from what they liked when sizing and this seems to work pretty well. Check with your plastic surgeon though because it does depend on the bra you size with and your starting point size wise.

 Difficult to generalize but, in my opinion, breast implants do tend to be compressed to some degree by the overlying tissues, including the pectoralis major muscle in most cases. Generally speaking, the best online advice I can give to ladies who are considering  breast augmentation surgery ( regarding breast implant size/profile selection) is: 
1. Concentrate on choosing your plastic surgeon carefully.  Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you're looking for. Ask to see lots of examples of his/her work.
2. Have a full discussion and communication regarding your   desired goals  with your plastic surgeon. This communication will be critical in determining which operation and/or breast implant size/type/profile will most likely help achieve your goals.
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or "C or D cup" etc means different things to different people and therefore prove unhelpful.
 Also, as you know, cup size varies depending on who makes the bra; therefore, discussing desired cup  size may also be inaccurate.  The use of computer imaging may be very helpful during this communication phase.
3.  Once you feel you have communicated your goals clearly,  allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals.  Again, in my practice, this decision is usually made during surgery.
I hope this, and the attached link, helps.

Thank you for your question.  Remember the breast implant sizer is placed on top of your breast inside of bra.  When the actual implant is placed inside youit is positioned differently and can looks smaller than the appearance of the sizer.

Trying sizers on is very helpful...not a perfect representation of final size, but better than any other technique we have and certainly better than letting a surgeon just chose the size THEY like.  The implants, when under your tissues, make look a little smaller, so we typically tell our patients to add 25cc or so to the sizer they like. But we also ask our patients to bring in photos from the internet to communicate how natural (or obviously implanted) a result they are seeking, and then we try sterile sizers in during surgery to see if they size the patient chooses will "fit" and is consistent with the shape they desire.

They may look a bit smaller but they certainly look different. Picking implants solely by their look in front of your skin is not very .helpful.