How do Breast Implants stay in place?

Thank for your inquiry.  The body creates a lining called a capsule which will surround the implant.  Hope that helps. Good Luck.

During
breast augmentation surgery, your plastic surgeon creates what we call a
surgical pocket that holds the implant in place. As your body heals from
surgery, a scar tissue capsule forms around the implant, which also helps
prevent a shift in position. Finally, the same supportive muscles and ligaments
that support the natural breast also help support an augmented breast. Larger
breasts as well as larger implants can lead to earlier sagging than women with
smaller breasts or implants may experience. The best way to ensure that your
implants are properly placed is to choose a board certified plastic surgeon who
specializes in breast augmentation.

Thanks for your question.  Basically, your tissues themselves.  When the implant is a scar sac (capsule) is formed around the device.  In most patients, this capsule will help keep the implant in place.  However, with age, time, gravity, and tissue stretch to age/pregnancy, the tissues will start to fall.   The extent varies widely between patients.  I have seen 55 y/o women with perky breasts and 22 year old women with very saggy breasts.  When the implant is placed under the muscle, the muscle helps keep the implant in place, but the breast tissues will sag and give the "snoopy breast."  If the implant is placed on top of the muscle, the breast and implant will fall together giving the "rock in a sock" look.  Some women, a few %, will not develop a good capsule and their tissues will stretch and "bottom out" early.  You cannot predict to whom this will occur.  Picking an appropriate sized implant and not over-dissecting the implant pocket are things that can be done to help avoid bottoming out. Good luck.  

A surgical pocket designed to fit and hold the breast implant is created under the breast. The body forms a membrane around the implant called a capsule to hold ther implant in place.