Washington ? Thirteen years after most silicone-gel breast implants were banned, federal health advisers on Tuesday narrowly rejected a manufacturer’s request to bring them back to the U.S. market, citing lingering questions about safety and durability.

Inamed Corp. had argued that today’s silicone implants are less likely to break and leak than versions sold years ago. But the Food and Drug Administration was skeptical, and its advisers voted 5-4 that the company hasn’t provided enough evidence about how long the implants will last — and what happens when they break and ooze silicone into the breast, or beyond.

Without that information, “How can we get an informed consent from our patients?” asked FDA adviser Dr. Amy Newburger, a New York dermatologist. “It makes me very uneasy. … I don’t feel secure about the safety.”

The FDA isn’t bound by its advisers’ recommendations — and the panel’s vote was a surprise. This same panel, with a few different members, had narrowly recommended allowing Inamed’s implants back on the market just 18 months ago, a decision the FDA rejected because of the durability concerns.

“Obviously we’re disappointed,” said Inamed Vice President Dan Cohen, who pledged to work with the FDA to get the necessary additional evidence as soon as possible.

That doesn’t mean the implants can never be sold, the advisers stressed. No one expects them to last a lifetime, but women need evidence about how likely they are to last 10 years, several panelists stressed.

But FDA adviser Dr. Michael Miller, a plastic surgeon at Houston’s M.D. Anderson Cancer Center who has used Inamed’s implants, argued the devices are being held to too high a standard.

“There are women who would benefit from these implants that don’t have access to them,” Miller said, complaining that salt water-filled implants sold without restriction today have their own drawbacks.

“All of us feel very strongly that women have a choice,” responded Dr. Barbara Manno of Louisiana State University. But she ultimately opposed lifting the ban because Inamed has tracked patients for only three or four years to check implant durability. She cited concerns that the older the implants get, the more likely they are to rupture.

Today, Inamed competitor Mentor Corp. will try to change the FDA panel’s mind. Mentor is seeking FDA approval of its own silicone implants, but hasn’t tracked patients any longer than Inamed did.

Silicone-gel implants were widely sold in the 1970s and ’80s until health concerns prompted the FDA in 1992 to limit their use to women in strict research studies.

The implants have largely been exonerated of causing such serious or chronic illnesses as cancer or lupus. But they can cause side effects, including infection and painful, rocklike scar tissue. Also, they can break, requiring additional surgery to remove or replace them — and the FDA and some panelists say questions remain about how often silicone then oozes into the body, and if it is harmful.

About 14 percent of the silicone implants will break within 10 years, Inamed officials told the FDA panel Tuesday, an estimate derived from a study of 940 patients tracked for three or four years.