There are two primary types of breast implants: saline-filled and silicone-gel-filled implants. Saline implants have a silicone elastomer shell filled with sterile saline liquid. Silicone gel implants have a silicone shell filled with a viscous silicone gel. There have been several alternative types of breast implants that were developed, such as polypropylene string or soy oil, but these are no longer manufactured.

History

Implants have been used since at least 1895 to augment the size or shape of women's breasts. The earliest known implant was attempted by Vincenz Czerny, using a woman's own adipose tissue (from a lipoma, a benign growth, on her back). Gersuny tried paraffin injections in 1889, with disastrous results. Subsequently, in the early to mid-1900s, a number of other substances were tried, including ivory, glass balls, ground rubber, ox cartilage, Terylene wool, gutta-percha, Dicora, polyethylene chips, polyvinyl alcohol-formaldehyde polymer sponge (Ivalon), Ivalon in a polyethylene sac, polyether foam sponge (Etheron), polyethylene tape (Polystan) or strips wound into a ball, polyester (polyurethane foam sponge) Silastic rubber, and teflon-silicone prostheses. In recent history, various creams and medicaments have been used in attempts to increase bust size, and Berson in 1945 and Maliniac in 1950 performed a flap-based augmentation by rotating the patient's chest wall tissue into the breast to add volume. Various synthetics were used throughout the 1950s and 1960s, including silicone injections, which an estimated 50,000 women received. Development of silicone granulomas and hardening of the breasts were in some cases so severe that women needed to have mastectomies for treatment. Women sometimes seek medical treatment for complications up to 30 years after receiving this type of injection.fact: date=July 2008

Breast Implants and FDA Approval

The standard implant in the United States has been saline-filled, ever since the FDA moratorium on silicone gel filled breast implants in 1992. Yet, silicone breast implants have not ceased to exist due to the popularity of the more natural feel offered by this type of implant.

Silicone gel-filled breast implants were first introduced in 1962. In 1976, the Medical Device Amendments were enacted, giving the FDA authority to regulate medical devices such as breast implants. In 1988, the FDA announced that all breast implants would be labeled as class III devices, meaning they are to be considered as medical breakthrough, new technology devices, and devices with poorly established or questionable safety and effectiveness. In addition, the FDA called for implant manufacturers to submit PMAs in which data showing the safety and effectiveness of these devices would have to be approved before the device could be placed on the market. Breast implants were now under careful scrutiny of the FDA. 1 In early 1992, the FDA placed a moratorium on silicone gel breast implants provided to the mainstream market for cosmetic purposes after many women who had received implants complained of pain and illness as a result of the implants leaking. The FDA concluded there was "inadequate information to demonstrate that breast implants were safe and effective." Access to silicone gel-filled breast implants continued to be allowed under controlled clinical studies for reconstruction after mastectomy, correction of congenital deformities, or replacement of ruptured silicone gel-filled implants due to medical or surgical reasons. Implant manufacturers were required to collect clinical trial data and were allowed distribution of the implants to a limited number of augmentation patients for these studies. 2