MAIN TYPES OF BREAST IMPLANTS

1. Saline -- silicone rubber shell filled with saline, or sterile salt water.

2. Silicone -- same type of shell filled with silicone gel.

WHAT IS SILICONE?

A manmade material, a combination of the elements silicon and oxygen.

Silicone is odorless and colorless.

It can stand up to high temperatures, water, chemicals and doesn't conduct electricity.

Silicone is used as a sealant, lubricant, adhesive and in breast implants.

WHAT IS SILICON?

Silicon is an element occurring in nature.

Silicon is the second most abundant element in the earth's crust, making 28 percent of it.

It's often mistaken for silicone. In the Shakira song "Objection", she sings "next to her cheap silicon I look minimal." That should probably be silicone.

ARGUMENTS FOR AND AGAINST SILICONE IMPLANTS

Against: women say leakage can cause intense pain, wipe out immune systems and leave people sick for much of the rest of their lives.

Against: studies by Inamed and Mentor say 1-20 percent of silicone implants rupture in 4 years.

Against: critics say there haven't been enough long term studies of silicone in women.

For: some say silicone implants are higher-quality products than saline implants.

For: supporters say women have a right to look at the evidence and decide for themselves.

For: they also say research shows no clear connection between tissue disease and the implants.

HISTORY

1960s: silicone breast implants are developed by two plastic surgeons in Texas.

1962: Timmie Jean Lindsey becomes first woman to receive silicone breast implants.

1988: FDA starts new rules, requiring breast implants be proven safe before sale.

1992: FDA calls for moratorium on silicone implants except for some research studies.

1992: four major companies get out of the implant business, following huge lawsuits.

1994: New England Journal of Medicine finds silicone implants don't increase risk of disorders.

By 1995, 20 studies show no link between disease and implants.

2003: FDA advisers recommend the ban on silicone implants be lifted.

January 2004: The Food and Drug Administration rejects a bid to bring silicone-gel breast implants back to the market.

April 2005: FDA advisers again recommend allowing silicone breast implants to return to the market.

SILICONE IMPLANT LAWSUITS

1977: Cleveland woman wins first lawsuit on ruptured implant. She wins $170,000 settlement.

1984: Maria Stern wins $1.7 million in total damages.

1991: One woman wins $7.3 million, another $5.4 million.

1992: Pamela Johnson wins $25 million in damages.

Several companies get out of the business: Dow Corning, Bristol-Myers Squibb and Bioplasty.

By 1995, Dow Corning alone was facing 20,000 lawsuits with 440,000 potential claims.

But soon, more research shows no link between implants and disease.

1996: California appeals court rules to dismiss 1,800 lawsuits against Dow Corning/Chemical.

Afterward, lawsuits go back and forth, more often in companies' favor.

Sources: FDA, British government report on silicone breast implants

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