Both Allergan and Mentor, the only two companies permitted to sell implants in the US, make low, medium or moderate and high profile implants. As implants move from low profile to high profile, the amount of projection increases and the base diameter decreases for any given volume. For instance, a Mentor 300cc high profile silicone implant has a base diameter of 11.1cm and a projection of 4.5cm. Whereas the Mentor 300cc low profile silicone implant has a base diameter of 13.5cm and a projection of 3.0cm.
Implants can either be round or shaped (also called anatomic, contoured or tear drop). For the most part shaped implants are used in breast reconstruction; there is no need for them in cosmetic breast augmentation. Shaped implants provide a breast shape when there isn’t any, such as following a mastectomy. These implants are textured to allow in-growth of the surrounding capsule because shaped implants have the potential to rotate causing problems and a need for revision surgery. This is also a reason not to use them in breast augmentation. The only real difference between the two companies is that there is slightly more projection with the Allergan implants than the Mentor implants for any given volume.
I have found that high profile implants tend to suit shorter, smaller framed women with a narrow base width and shorter collar bone to breast mound distance. Conversely low profile implants are great to give upper pole fullness in augmentation mastopexy or to add fullness with less added projection in women with adequate breast tissue.
A basic appreciation of the various styles of implants is necessary in overall patient education. However, it is your surgeon’s expertise and experience that will guide him or her toward a particular implant for you. Ask about the reasons for choosing a particular implant and don’t be afraid to get all of your questions answered before the decision is final.