WASHINGTON — A Food and Drug Administration advisory panel recommended yesterday that silicone-gel breast implants made by Mentor be allowed back on the market for wider use — a surprise decision that came one day after the same panel rejected the application of a rival company.

The panel voted 7-2 in favor of lifting a 13-year-old partial ban on the controversial implants, but advisers also recommended that the company be required to meet nine tough conditions.

Yesterday's vote, coming after the panel rejected the application of Inamed by a 5-4 vote, gives the FDA a mixed recommendation as it grapples with the future of the devices, used for breast enlargement and reconstructive surgery.

The FDA ordered the silicone devices off the market in 1992 amid controversy about health problems experienced by women who had the implants. Many women had complained of fatigue and sometimes-severe joint and muscle problems after receiving implants.

In 2003, the FDA rejected an earlier advisory panel's recommendation to allow general use of silicone-gel implants, and the agency could decide now to approve one company's device, both companies' devices or neither of them.

Mentor officials were delighted by the panel vote.

"We're very gratified that the panel came to the decision they did and hopeful the agency will focus on the same things: the quality of our science and the quality of our data on safety and efficacy," said Joshua Levine, president and chief executive of the Santa Barbara, Calif.-based company. "I think the panel concluded that not all breast implants are created equally and not all test methods are created equally," Levine said.

In explaining their decision, several panel members said they were more impressed by Mentor's data on how and why implants rupture and by the lower rupture rate of its implants.

While Inamed, also based in Santa Barbara, reported a yearly rupture rate of about 1.4 percent, the yearly Mentor rate was 0.2 percent — a figure that had been questioned by FDA reviewers.

The panel's decision was questioned sharply by Inamed officials, who had been criticized the previous day for not having sufficiently long-term data.

"Inamed views today's panel decision as curious and inconsistent with the decision reached by the panel yesterday on Inamed's (application) — we look forward to working with Dr. (Lester) Crawford and FDA staff on addressing these inconsistencies," Inamed president and chief executive Nicholas Teti said in a statement after the meeting in Gaithersburg, Md.

About 260,000 American women had their breasts enlarged with implants last year, and an additional 60,000 had received them after surgery for breast cancer. Because of health concerns, the FDA in recent years has allowed silicone-gel implants to be used only in women who had mastectomies and in some who take part in clinical trials; all others received implants filled with a saline solution. Many women say the silicone gel looks and feels more natural, and it is widely used in other parts of the world.

The panel's decision also was criticized by some public-interest groups that long have argued that the potential dangers of silicone-gel implants remain insufficiently studied.

"I think this was a triumph of wishful thinking, which overruled the lack of science," said Diana Zuckerman, president of the National Center for Policy Research for Women and Families. "Because of all the conditions, it's far from a done deal regarding the FDA. It's not helpful to women to have a product approved on the basis of two years of safety data."

Among the conditions recommended by the panel are that the company allow its devices to be implanted only by certified plastic surgeons who have worked with the devices previously; that a major study of the implants be continued until the devices have been in use for 10 years; and that the implants be subject to another FDA review in five years.

Dr. Laurie Casas, a plastic surgeon and spokeswoman for the American Society for Aesthetic Plastic Surgery, said her organization would be working with plastic surgeons to set up a new certification program.

"We'll be working with the manufacturer and the FDA to fulfill whatever the agency requires to allow women to finally have a choice," she said. "We're very, very happy about this. Our hands have been tied for so long."

The FDA is required to make a decision about the implants within 90 days.

The Los Angeles Times contributed to this report.