There are four general types of breast implants, defined by their filler material: saline solution, silicone gel, structured and composite filler. The saline implant has an elastomer silicone shell filled with sterile saline solution during surgery; the silicone implant has an elastomer silicone shell pre-filled with viscous silicone gel; structured implants use nested elastomer silicone shells and two saline filled lumen; and the alternative composition implants featured miscellaneous fillers, such as soy oil, polypropylene string, etc. Composite implants are typically not recommended for use anymore and, in fact, their use is banned in the United States and Europe due to associated health risks and complications.
the second technological development was a polyurethane foam coating for the shell of the breast implant; the coating reduced the incidence of capsular contracture, by causing an inflammatory reaction that impeded the formation of a capsule of fibrous collagen tissue around the breast implant. Nevertheless, despite that prophylactic measure, the medical use of polyurethane-coated breast implants was briefly discontinued, because of the potential health-risk posed by 2,4-toluenediamine (TDA), a carcinogenic by-product of the chemical breakdown of the polyurethane foam coating of the breast implant.
It has been shown that the rates of capsular contraction are much lower when the breast implant is placed below the muscle. Also, with the implant below the muscle, there is that extra layer of tissue between the visible part of the breast and the implant, therefore making it more difficult to be detected by touch and maintain the natural feeling of the breast. The breast will look more natural with this method as you will not be able to visibly see the edges of the implant.
In 2000, the FDA approved saline breast implant Premarket Approval Applications (PMA) containing the type and rate data of the local medical complications experienced by the breast surgery patients. "Despite complications experienced by some women, the majority of those women still in the Inamed Corporation and Mentor Corporation studies, after three years, reported being satisfied with their implants." The premarket approvals were granted for breast augmentation, for women at least 18 years old, and for women requiring breast reconstruction.
Another option is to consider getting your breast implants at a teaching hospital from a learning resident. You won’t get the delicate skill of an experienced, board-certified surgeon, but teaching hospital residents are “assisted by established, experienced, private attending surgeons,” says Beverly Hills plastic surgeon Dr. Robin T.W. Yuan in a RealSelf Q&A.
Saline filled breast implants consist of a silicone elastomer (rubber) shell that is filled with a sterile saline solution at the time of surgery. Saline breast implants come in a wide range of sizes and are available with both moderate and high profiles (the amount of projection of the breast silhouette). Most women choose round implants, but contoured, or shaped, styles are also available and may be recommended for women with smaller breasts. Contoured implants are made with a textured surface designed to keep them from turning and losing their shape. A new style of round implant is Mentor's post-operatively adjustable implants, which can be adjusted in size up to 6 months after surgery.