Cohesive Gel Breast Implants


Form stable cohesive gel breast implants differ from the round breast implants that the FDA approved in 2006.  These implants, which have been given the nickname “Gummy Bear” implants over the years, are the newest generation of silicone gel breast implants. In March of 2012, Sientra became the first US manufacturer to obtain FDA approval for the sale of their version of the shaped form stable breast implant.  Form stable breast implants, manufactured by Mentor and Allergan are currently considered investigational devices in New Jersey and the US and are not yet FDA approved. Developed in the early 90’s, and used widely throughout the rest of the world, the Style 410 manufactured by Allergan, and the CPG manufactured by Mentor,  remain in clinical trials in the United States until their anticipated FDA approval.  Although each of these manufacturers has developed a form stable cohesive gel implant, they differ from each other with respect to the consistency of their fill (cohesivity), their shape, and the percentage of gel that they are each filled with.

I am presently continuing to enroll patients in the Allergan style 410 studies, until their anticipated approval by the FDA.  Because the value of these studies is so significant, Allergan encouraged specialized training in the use of their devices, and I underwent extensive training in Sweden before being given the opportunity to enroll patients for study. I have now been enrolling patients since 2005 and have extensive experience with form stable breast implants. In the United States there are presently two groups of patients who may enroll in a clinical trial with the form stable cohesive breast implants. The first group are women who request a revision breast augmentation or breast reconstruction after mastectomy (CARE study), and second, are those women who desire a primary breast augmentation (410 implant study). All patients must agree to return for scheduled follow-up exams for a period of 10 years from the date of their surgery. After their FDA approval, there will still be a need to continue long term follow-up of augmentation, reconstruction, and revision augmentation patients, in order to collect long-term data on surgical outcomes.

Frequently Asked Questions

How are form stable highly cohesive breast implants different from standard round gel implants approved in 2006?

Cohesivity: The more cohesive silicone gel is, the thicker and firmer it becomes. This explains why silicone can come in a liquid form, like in your hair gel, as well as the solid form like your kitchen cutting board. There is a range of firmness within silicone products, and the form stable cohesive gel implants are believed to be just firm enough to resist forming creases and folds, yet soft enough to feel like a natural breast. Each of the different manufacturers, Allergan, Mentor, and Sientra, have designed form stable breast implants with different degrees of cohesivity. The increased form stability of these breast implants may lead to reduced implant visibility and palpability through the overlying breast tissue and skin.

Shape: The form stable cohesive gels offer plastic surgeons and their patients the opportunity to select shaped breast implants. This means that the breast implants have a variable width, height, and projection. The possible advantage to a shaped device is that it offers plastic surgeons more options in selecting an implant that can fit your individual body shape and size, as well as the quality of your breast tissue. Shaped form stable breast implants are especially useful for patients with breast or chest wall asymmetries, or patients with tuberous or constricted base breasts. No one breast implant is the right one for all women. Some may still prefer the fuller look of a round implant while others may prefer a more proportionate breast augmentation.

Rupture Rates and Capsular Contracture: The 7 year data collected from the United States, as well as the data collected from Europe and Canada, shows very low rupture rates with the form stable cohesive gel devices. More data will continue to be collected over the next 10 years.

Will I need a larger incision if I choose form stable gel implants?

Because these implants cannot be folded on themselves, the surgeon must use a slightly larger incision to place these implants into the body without damaging the implant shell or the cohesive gel. Incision sites should be discussed with the surgeon.

Do I need to have an up-to-date mammogram prior to undergoing this procedure and what screening techniques are used after?

Mammography and MRI: Your breast health should be your primary concern. Pre-operative mammography is strongly suggested on all patients over 35 and as indicated by the American Cancer Society guidelines thereafter. After breast augmentation, specialized views may be necessary for women with breast implants. Presently, an MRI is the best technique routinely available for evaluating the integrity of breast implants, but newer High Resolution ultrasound techniques are on the horizon.

How can I enroll in a form stable highly cohesive gel breast implant study?

Until their FDA approval in the United States, patients must enroll in a FDA approved long-term study to obtain the form stable implants manufactured by Allergan and Mentor. The Sientra form stable breast implants are presently available with voluntary long-term study enrollment. As a requirement of these studies, patients are encouraged to return for scheduled visits over a ten year period. Patients interested in enrollment can visit or and click on “find a cohesive breast implant surgeon” to locate a highly experienced board certified plastic surgeon in your region of the country.

Are form stable breast implants ideal for all patients?

There are advantages and disadvantages to all breast implants. A careful breast exam and lengthy consultation are necessary to determine the best breast implant for you. Additional assessment of your breasts can also be performed with the Vectra 3D simulation. This gives women the opportunity to visualize several different breast implant options and creates a better educated patient.


Source Caroline Glicksman, MD



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