WASHINGTON — Silicone-gel filled breast implants are a step closer to returning to the market. The Food and Drug Administration on Thursday told Mentor Corp. that its implants meet the criteria for approval, one of several steps on the way to a final OK. The company still must meet certain conditions before the implants are allowed back on the market.

"We are very encouraged by this communication from the FDA, and view this letter as a positive sign for women and their surgeons that another option will soon be available," said Joshua H. Levine, president of the Santa Barbara, Calif.-based company.

The implants have been banned for 13 years because of health concerns. On April 13, an FDA advisory committee voted 7-2 to recommend allowing them back on the market under certain conditions.

Among those conditions were ensuring that women understand the devices may break silently inside their bodies; recommending that women get regular MRI exams to check for those breaks; allowing only specially training plastic surgeons to be able to perform implant insertions; and requiring new studies to prove how long implants last

The FDA said it is not allowed to reveal the contents of its letter to Mentor. But the company said the conditions outlined in the letter generally are consistent with the advisory panel's recommendations.

Also Thursday, a group of seven female senators led by Sens. Dianne Feinstein, D-Calif. and Olympia Snowe, R-Maine, urged the FDA to consider women's safety before the agency makes a final decision.

The silicone implants were banned in 1992 because of concerns that ruptured implants could cause illness in women.

The FDA advisers voted in favor of allowing the Mentor implants back on the market just a day after turning down a request from a competitor, Inamed Corp.

Women who have sought return of the product say silicone-gel implants look and feel more natural than the salt water-filled implants sold without restriction.

But other women told the advisory panel about silicone oozing out of their bodies and of years of pain and other symptoms, which they blame on faulty implants.

Silicone-gel breast implants first went on the market in 1962, before the FDA required proof that all medical devices are safe and effective.

The implants largely have been exonerated of concerns that they might cause serious or chronic illnesses such as cancer or lupus. But aside from the risk of breakage, they can cause infection and painful scar tissue.

About 264,000 breast enlargements and 63,000 breast reconstructions were performed in the United States last year.

On the Net:

Food and Drug Administration: http://www.fda.gov

Mentor: http://www.mentorcorp.com/