FRIDAY, March 9 (HealthDay News) -- A new silicone-gel breast implant received conditional approval Friday from the U.S. Food and Drug Administration. The implant can be used for breast augmentation in women 22 and older and for breast tissue reconstruction at any age.

The newest implant, manufactured by Sientra of Santa Barbara, Calif., becomes the third approved for use in the United States, joining devices made by Allergan and Mentor. As a condition for approval, Sientra will continue studies on the implant's long-term safety, effectiveness and risks of rare diseases, the FDA noted.

"Data on these and other approved silicone-gel filled breast implants continue to demonstrate a reasonable assurance of safety and effectiveness," Dr. William Maisel, deputy director for science in the FDA's Center for Devices and Radiological Health, said in an agency news release.

Silicone breast implants have been controversial for years, with critics contending that the devices can rupture and leak silicone, potentially causing a variety of health problems, including cancer and lupus.

Classified as medical devices, silicone implants are surgically placed under breast tissue or chest muscle to reconstruct or augment the breast.

In reconstruction, the implant usually replaces breast tissue removed because of cancer or trauma or breast tissue affected by a severe breast abnormality. Another reason is to revise or improve results from a previous reconstruction surgery, according to the FDA.

Similarly, breast augmentation is used to increase breast size or to improve on previous augmentation surgery.

The FDA approval of Sientra's implant is based on three years of data from clinical studies on nearly 1,800 patients. Complications included tightening of the area around the implant, re-operation, implant removal, uneven appearance and infection, according to the agency's release.

The company's additional long-term studies will include a seven-year follow-up of the current participants; a 10-year study of nearly 5,000 women to monitor long-term complications, including rheumatoid arthritis, breast and lung cancer; and five studies focusing on possible links between the new implant and connective tissue and neurological diseases, brain cancer, cervical/valvular cancer and lymphoma, the FDA said.

Reaction to the latest approval came swiftly.

Dr. John Oeltjen, an assistant professor of plastic surgery at the University of Miami School of Medicine, thinks the FDA decision is a good one.

"The implant from Sientra is like the implants from other companies already marketing implants," he said. "So that's not out of line."

"In general, there are no problems with silicon gel implants," he said. The advantage of silicon gel over saline implants is that the silicon has a more natural look and feel, he added, while saline implants can wrinkle, which can show through the skin.

However, Oeltjen said he would like to see the FDA also allow marketing of contoured implants, which are not round, but shaped more like a natural breast.

Dr. Jeffrey C. Salomon, a clinical professor of plastic surgery at Yale University School of Medicine, noted, "Sientra is a brand that has been used in Brazil for an extended length of time, and I doubt that there were concerns about cancer, otherwise the FDA would have not approved them."

He added, "While the next generation of breast implants is the so-called form stable variety, those implants have not been released in the U.S. despite being used throughout the world for a few years."

"The form stable implant does not develop capsular contracture, which is a response by the body to a foreign object and can result in pain and discomfort as the implant is squeezed by fibers created by the immune system," he added. "And that is really the category of breast implant surgeons are anticipating the release of."

Dr. Alan Matarasso, a plastic surgeon at Lenox Hill Hospital and Manhattan Eye, Ear and Throat Institute in New York City, said: "This [the FDA decision] is exciting information for patients because it offers another choice for women undergoing breast cancer reconstruction or cosmetic breast augmentation."

Silicone gel implants had been banned in the United States for 14 years, until 2006 when the FDA approved the ones made by Allergan and Mentor for breast reconstructive surgery and for breast enlargement in women 22 and older.

But, when the ban was lifted, the FDA noted that there wasn't a lot of data on adverse effects, including what the agency called "rare events" and "long-term performance." In light of this, the agency required the manufacturers to do studies on the implants' safety and performance after their approval.

Then last September, after a contentious two-day hearing, the FDA ruled that silicone implants were safe and could remain on the market. However, the agency said at the time that it would work with manufacturers of the devices approved for use in the United States to improve studies gauging the health of women who received the implants.

The FDA emphasized last year that silicone implants don't last forever, with as many as half of women with such implants requiring removal within 10 years of the initial surgery. According to the agency, one in five women who receives silicone implants to increase the size of her breasts will need to have the devices removed within 10 years due to complications. And as many as half of women who receive implants for reconstruction after breast surgery will need them removed within the same time frame.

Common complications include: hardening of the area around the implant; the need for additional surgeries; and implant removal. Other frequent problems include implant rupture, wrinkling, breast asymmetry, scarring, pain and infection, the FDA said.

The FDA recommends that women who get silicone implants: follow-up regularly with their doctor, which includes occasional MRIs to detect potential ruptures; pay attention to any changes and notify their health-care provider if they notice any unusual symptoms such as pain, asymmetry or swelling; and educate themselves on the signs and symptoms of complications.

"It's important to remember that breast implants are not lifetime devices," Maisel said. "Women should fully understand risks associated with breast implants before considering augmentation or reconstruction surgery, and recognize that long-term monitoring is essential."

According to FDA estimates, 5 million to 10 million women worldwide have breast implants.

More information

The U.S. Food and Drug Administration has more about breast implants.