Silicone Gel Breast Implants Detailed Information

1. Breast Implant Fill - Saline or silicone?

Silicone Gel Filled Breast Implants Basics

What's the story with "gummy bear" implants? Click here to find out.

History & Controversy

Breast implants have always been controversial but silicone has been especially controversial. In a world where organizations like NOW Advocate Abortion for women and people can choose to smoke and drink, it is puzzling that so much effort has gone into taking away the rights of women to choose silicone breast implants on claims that they will harm us and that we can't decide what's best for us.

Detour: What is silicone?

Starting in the late 1980's and culminating with the early 90's ban on silicone implants, women have claimed to get all types of illnesses from silicone gel breast implants. Claims initially included a connection between silicone gel breast implants and autoimmune diseases, connective tissue diseases and even cancer. Class action suits were filed wherein 1,000s of women claimed that their symptoms of scleroderma, rheumatoid arthritis, chronic fatigue, hair loss, breast and other cancers, were caused by leaking silicone implants. As a result of the claims, and without any conclusive scientific evidence, the FDA imposed a ban on the sale of silicone gel breast implants in 1992, meaning that silicone breast implants would no longer be available for the general public. In the wake of the claims, companies paid millions of dollars in lawsuit settlements and some filed for bankruptcy, despite a lack of any studies to back up the claims. The FDA allowed silicone gel implants to remain in use after 1992, but only if a patient met certain criteria and was also enrolled in a study. In April of 2005, after hearing testimony from women and reviewing the available studies and data, the FDA's scientific panel, voted 7-2 that FDA should approve Mentor's gel implants but voted 5-4 that FDA should not approve the Inamed gel implants. On July 28, 2005, Mentor received an "approvable" letter from FDA, indicating that Mentor's silicone gel implants could be approved if Mentor met certain conditions. Inamed (now Allergan) ultimately received a similar "approvable" letter.

Read more on the FDA approvable letters for silicone gel breast implants.

On November 17, 2006, after a year and a half of follow ups and further negotiation with the manufacturers regarding what conditions would be imposed, the FDA approved certain silicone gel breast implants for breast augmentation in women aged 22 and over. Not all silicone implants are included in the approval and you should ask your doctor which implants are available. Today's silicone gel breast implants are made differently than they were in the 1970s and 1980s. Initially, silicone gel breast implants had thick shells and thick silicone gel fills. In the 1970's, manufacturers began to use thinner shells, which were more likely to rupture. Today, both Mentor and Inamed make silicone implants with multiple layers of silicone elastomer surrounding the implant. This reduces the amount of gel bleed but can make the implants feel and look firmer. They are, however, much softer than saline. Unlike saline breast implants, silicone gel breast implants are pre-filled. Surgeons order them in the requested size and they cannot be changed. Plastic surgeons have to make longer incisions in most cases to place a silicone gel filled breast implant than a saline filled breast implant, all other things being equal. Silicone breast implants cannot be placed endoscopically through a navel incision.

Is Silicone Safe? Studies about Silicone Gel Breast Implants

Numerous studies have been conducted to see if the anecdotal claims of women about their silicone breast implants were verifiable by scientific evidence. These studies have found localized risks associated with all breast implants, but no conclusive evidence to support the claims against implant manufacturers as noted above. Many studies conducted by the Institute of Medicine and other experts have found no connection between breast implants and the diseases claimed by so many women.

Here is what the Mayo Clinic has to say on their website. "Breast implants don't increase your risk of breast cancer. The IOM reviewed evidence that breast implants don't cause breast cancer or the recurrence of breast cancer. However, it's still essential that you undergo routine screening for breast cancer — breast self-exams, mammograms and clinical breast exams — just as you would if you didn't have implantsBreast implants don't weaken your immune system. When your body detects something foreign in your system, such as a virus or bacteria, it responds by kicking your immune system into high gear. However, the IOM found no evidence to suggest this happens with breast implants. Nor did it find evidence linking implants to any sort of autoimmune or connective tissue disorder. Breast-feeding is safe. If your breast milk has absorbed some of the silicone from the implants, don't worry. Your baby isn't in danger. Because breast milk is the best thing you can feed your baby, the IOM encourages women with implants to breast-feed." Additionally, the American Medical Association reported a Swedish study in February 1998 that there was no link to connective tissue disease.

The FDA has conducted a study where they conclude that extra capsular silicone (from a ruptured implant) can be associated with fibromyalgia. The study relied on a survey of 344 women who filled out surveys asking about their symptoms. Women who reported they had the symptoms were then checked to see if their implants had ruptured. Based on the women reporting symptoms and having ruptured breast implants, the study assumed a connection. Unfortunately, that is how the plaintiffs prevailed in numerous lawsuits, with no evidence of a cause and effect, just a demonstration of coincidence. More recent studies have also found that women with implants are more likely to commit suicide and more likely to have certain brain cancers. These women might also be more likely to skydive, ride mechanical bulls and bark at the moon but none of the studies showed a cause and effect, just coincidence. Studies have found no link between implants and breast cancer, other than the fact that implants can interfere with detection because of interference with mammography.

Detour:  Read the studies below about Silicone Gel Breast Implants, for yourself!
Institute of Medicine Report | U.K. Independent Review Group | Court-Appointed National Science Panel for Class Action Suit British Journal of Medicine FDA Website | Swedish Cohort Study

Who Qualifies for Silicone Breast Implants?

Prior to the FDA approval on November 17, 2006, silicone gel breast implants were not available for general use and women could only obtain silicone breast implants as part of an FDA-sanctioned study such as the Silicone Adjunct Study which is now closed. As of November 17, 2006, women aged 22 and over qualify for the silicone gel breast implants manufactured by Mentor Corp. and Inamed. Not all silicone gel breast implants made by these manufacturers have been approved. According to Mentor's website, eligibility is as follows:

Mentor MemoryGel Silicone Gel-Filled Breast Implants are indicated for females for the following uses (procedures):

  • Breast augmentation for women at least 22 years old. Breast augmentation includes primary breast augmentation to increase the breast size, as well as revision surgery to correct or improve the result of a primary breast augmentation surgery.
  • Breast reconstruction. Breast reconstruction includes primary reconstruction to replace breast tissue that has been removed due to cancer or trauma or that has failed to develop properly due to a severe breast abnormality. Breast reconstruction also includes revision surgery to correct or improve the result of a primary breast reconstruction surgery. (A separate patient brochure is available for and should be read for breast reconstruction.)

Mentor’s silicone gel-filled breast implants, referred to as MemoryGel products, come in a variety of profiles and sizes. Mentor's Lumera and Becker gel implants were not approved at this time. Get specific details on the available breast implant sizes, shapes, etc. in our manufacturer's section. Click here or follow the links at the end of this page. Prior to FDA approval, only these patients could obtain silicone breast implants:

  • Mastectomy patients undergoing reconstructive breast surgery.
  • Patients having surgery due to less than desirable results with saline. (Capsular contracture , rippling , etc.)
  • Patients having a breast lift (mastopexy), in addition to breast augmentation.
  • Patients with certain chest wall deformities (pectus excavatum, pectus carinatum , possibly scoliosis).

What about those "Cohesive Gel" and "Gummy Bear" Silicone Gel Breast Implants?

First of all, the so-called "gummy bear" implants were NOT approved by the FDA in November of 2006. Allergan, Mentor and Silimed each have a trial underway in which qualified patients can get the "gummies" as part of a trial. Ask your doctor if you qualify. Mentor and Allergan have applications in to the FDA for approval. Also, if you are in Canada or Europe, you can get them.

What is a "gummy bear" implantGummy bear is not an official term but more of a slang that has evolved for certain implants that are 'so' cohesive that they actually retain their form. It should be noted that all silicone gel implants are "cohesive", which means that silicone is not loose, like water, for example. (Detour: Read more on the meaning of "cohesive"). But, cohesive does not mean that the silicone is not a liquid, which can leak when a breast implant breaks. In order to improve on the silicone implants of the 70s and 80s, which were runnier than today's silicone cohesive breast implants were invented in the early 1990s.

The current name "gummy bear" is given by many patients and doctors to implants that are "form-stable". This means that they are so cohesive, that they are more a solid than a liquid (see photo at left). These form-stable implants have the purpose of making a longer lasting implant that maintains a more attractive and predictable shape. As such, the the gel is less liquid-like and more solid-like than even today's other cohesive silicone gel implants. Gummy bear (form stable) implants are available in Europe from Allergan (the model 410), Mentor (the CPG) and Silimed. Canada also approved them for use along with other silicone implants in 2006. Almost all of the form stable implants are anatomical in shape. CUI (a company in Europe now owned by Inamed) makes a round form stable implant but they are only appropriate for a limited number of patients. It should be noted that there is a slippery slope when it comes to "cohesive." Allergan's 410 (a so-called "gummy" because of its form stable properties), also comes in a "soft touch" model, which is a little less cohesive. Whether the soft touch has enough stability to deserve the name "gummy" is a bit of a debate so discuss this with your doctor if you're looking for a true gummy bear breast implant.

Advantages of the so-called "gummy bear" (form stable) Cohesive Gel Implant


Cohesive implants may maintain their shape better than other silicones and thereby impart their shape upon the breast. Saline or standard silicone gel are subject to the forces of gravity and shape of the breast, so that they assume the shape that the forces of the breast and the forces of gravity dictate. Cohesive gel implants have a distinct shape, and they will impart it upon the visible shape of the breast.

Folds and Rippling- Since the fill does not shift from one area of the shell to the other, shell collapse and folds do not seem to occur, even in long term follow up.

Won't Leak

There are 2 components to this issue. One is whether the shell might break, and the other is whether the gel will leak out if the shell does break. The shell is certainly physically susceptible to breakage, but since most ruptures are believed to occur along shell folds (they result in weakening of the shell, much like a folded newspaper left in a drawer will crack along its folds), it is expected that shell failures will occur less frequently. If it does occur, the fill, more solid than liquid, is less likely to move.

Capsular Contracture

The European experience has been that firm scar tissue seems to occur less often with cohesive implants (capsular contracture). It is not clear if this will be maintained over time, or what the cause is. Some speculate that it is related to there being less diffusion of silicone than with non-cohesive fillers, while others believe it is due to the increased firmness of the implant, which inhibits the body from contracting around it. More time and study will be necessary before we know the answer to this issue.

Disadvantages of the so-called "gummy bear" Cohesive Gel Implant


Since it will impart its shape upon the breast, the patient and surgeon had better be sure that they are choosing an implant shape that they want the breast to have. While implant selection certainly matters with old style silicone gel and saline implants, since their shape so so affected by gravity and forces of the breast, there is a great margin for error.


These implants do feel a little bit firmer than old style silicone gel implants (though if the old ones get a capsular contracture, they will feel firmer…some believe that the cohesives are less likely to get such a contracture, but that is not yet known). How significant this is in a given patient depends upon how much breast tissue they have relative to how large an implant will be chosen, and how firm or loose their tissue feels. A rare patient will complain about the firmness, but for most patients, particularly those getting implants that are not oversized, this is not an issue.


These implants do cost significantly more than saline, and several hundred dollars more per pair than old style silicone gel implants. However, if part of the study, patients will be reimbursed most of the implant cost over a period of ten years.

Incision Size

Since these implants are not deformable, they cannot be squeezed through little incisions. Depending upon the size of the implant, incision length must be between 4.5-5.5 cm. It also can make insertion from around the areola difficult
(I usually use the underneath incision with the cohesive implants). Armpit incision is possible, but exceedingly difficult.


Many cohesive gel implants sold as "gummy bear" implants, such as Inamed's entire 410 series of cohesive implants only come in anatomical shapes, meaning that they project more on the bottom than they do on the top. One of the risks of such a design is that if the implant rotates in the body, it will create a distortion. Care is taken during pocket dissection and insertion in order to minimize this. It is a very rare, but very possible complication. The only way to fix it if it occurs is to remove them and replace them with a round implant. Rotation is at greater risk when the tissue is loose, for instance in a revision when a patient wants to go smaller.

Gel Fracture

Since the gel is almost a solid, it can actually crack. I have only seen this happen from excessive manipulation of the implant outside of the body, but it can theoretically occur in the body. No one knows if this can actually occur, or what the consequences would be if it were to occur. My speculation is that it would not be noticed, but the answer to this is not yet known.

NOTE: Keep in mind that these characteristics are of the gummy bear cohesive implants and are not characteristics of today's other silicone gel breast implants, which have a cohesive nature, but are more liquid than solid.

Many thanks to Dr. Steven Teitelbaum for this information on Cohesive Gel Breast Implants.

Breast Implants: The Full Roadmap

1. Breast Implant Fill - Saline or silicone?

  • Saline
  • Silicone
  • History & Controversy
  • Studies about Silicone Gel Breast Implants
  • Who Qualifies for Silicone Breast Implants
  • Cohesive Gel and Gummy Bear Silicone Breast Implants

2. Breast Implant Size - How do I choose the right size?

  • Methods of determining ideal breast implant size choice
  • Using Nicole's photo gallery to help choose size
  • Choosing from breast implant manufacturer specifications

3. Breast Implant Shape

  • Choosing Breast Implant Shape and Profile
  • Breast Implant Shapes: Round vs. Anatomical (teardrop/contoured/shaped)
  • Breast Implant Profile: Low, Moderate, High

4. Breast Implant Surface

  • Textured Surface Breast Implants
  • Smooth Surface Breast Implants

5. Breast Implant Profile

  • Moderate profile breast implants (regular/standard)
  • High profile breast implants
  • Low profile breast implants
  • Moderate "PLUS" profile breast implants

6. Breast Implant Manufacturers

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