Mentor Core Gel Breast Implant Study

Updated on: November 11, 2015

Mentor is conducting a clinical study to evaluate the safety and effectiveness of our silicone gel-filled mammary implants. In this nationwide study, 1,000 patients enrolled at up to 60 study sites will be implanted with Mentor silicone gel-filled breast implants and followed for 10 years.

The study follows three groups of patients, those seeking implants for general breast enlargement (Augmentation); those who are undergoing breast reconstruction (Reconstruction); and those patients that need a revision of a previous saline or silicone gel breast implant (Revision).

Silicone gel breast implants have not been generally available since 1992, when the Food and Drug Administration (FDA) required implant manufacturers to collect clinical trial data. This core study will provide the required information to FDA. While all patients will be followed for ten years, Mentor will submit two-year data to FDA in a Premarket Approval (PMA) application to demonstrate the safety and effectiveness of our silicone gel breast implants.

Alternative products and surgical options to silicone gel-filled breast implants are limited. These options include saline-filled breast implants for augmentation and reconstruction procedures, as well as autologous tissue, which utilize the patient's own tissue during reconstruction procedures.

Current Status
Patient enrollment for this study is complete. All patients are currently being seen for their required postoperative follow up.

The following information is the Informed Consent that patients received when they were entered into the Mentor Core Gel Study for silicone breast implants. As you can see, women are much more informed regarding the risks and benefits of breast implants. The breast implant study information provided here is very thorough, and informative.

Mentor Core Gel Silicone Breast Implant Study Informed Consent


291 Mentor Drive
Santa Barbara, CA 93111, USA

Participation as a Research Subject in the "Study of the Safety and Effectiveness of the Mentor Round Low-Bleed Silicone Gel-filled Mammary Prostheses in Women Undergoing Primary Breast Augmentation, Reconstruction, or Revision (Core Gel Study)"


This study is being sponsored by Mentor, a manufacturer of plastic surgery products. The purpose of this study is to determine the safety and effectiveness of the smooth and textured surface Mentor Round Low-Bleed Silicone-filled Mammary Prostheses in women who are undergoing primary breast augmentation, primary breast reconstruction, or revision. For example, safety information on the rate of capsular contracture, rupture, and infection will be collected, and used to help determine device safety. These implants are investigational devices.
Approximately 1000 patients at centers across the United States will be enrolled in this research study. These patients will be implanted with silicone breast prostheses and monitored for ten years to collect information on risks associated with the implant surgery as well as changes in the way these patients feel about themselves.

Breast implants have been used in nearly two million women since the early 1960's. There are known risks and potential complications from having breast implants. Since 1992, the Food and Drug Administration (FDA) has allowed limited silicone gel implant studies of breast reconstruction after mastectomy for cancer, correction of deformities, or replacement of damaged implants. The FDA has not formally approved these gel-filled breast implants as safe and effective because additional scientific evidence needs to be collected.


You will be allowed to enter the study if the following criteria are met:

  • You were born female and are 18 years of age or older.
  • Are a candidate for one of the following:
    Primary breast augmentation (general breast enlargement or sagging after breastfeeding)
    Primary breast reconstruction (for cancer, trauma, surgical loss of breast, or congenital deformity)
    Revision surgery (if you currently have a silicone filled implant or a saline filled implant
    Sign the Informed Consent
    Agree to follow the procedures for explant analysis
    Agree to comply with the follow-up procedures, including returning for all follow-up visits.

    You will not be allowed to enter the study if you meet any of the following criteria:
  • You are pregnant.
  • Have nursed a child within three months of this study enrollment.
  • Have been implanted with any silicone implant other than breast implants (e.g. silicone artificial joints or facial implants)
  • Have a confirmed diagnosis of the following rheumatic diseases or syndromes: SLE, Sjogren's syndrome, scleroderma, polymyositis, or any connective tissue disorder, rheumatoid arthritis, crystalline arthritis, infections arthritis, spondyarthropathies, or any other inflammatory arthritis, osteoarthritis, fibromyalgia, or chronic fatigue syndrome.
  • Currently have a condition that could increase risk or complicate wound healing (except reconstruction patients)
  • Are an augmentation patient and have had a diagnosis of cancer of any type.
  • Have an infection or an accumulation of pus in a body tissue (abscess), anywhere in the body.
  • Have a tissue condition that is clinically incompatible with the implant (e.g. tissue damage resulting from radiation, inadequate tissue, or compromised vascularity)
  • Have any condition, or are under treatment for any condition, that your doctor determines to be an unwarranted risk.
  • Have a physical abnormality that could lead to significant postoperative complications.
  • Have characteristics that are unrealistic/unreasonable with the risks involved with the surgical procedure.
  • Have a premalignant breast disease without a subcutaneous mastectomy.
  • Have untreated or inappropriately treated breast cancer, without mastectomy
  • Have an implanted metal or metal devices, history of claustrophobia, or other condition that would make a MRI scan prohibitive.

Two types of Mentor Round Low-Bleed Silicone Gel-filled Mammary Prostheses will be used in the study: the Siltex textured surface device and the smooth surface device. Each implant is a silicone elastomer (rubber) mammary device that is supplied individually packaged in a double wrapped packaging system, sterile, and non-pyrogenic (does not cause fever). Each device consists of a silicone shell encasing a silicone gel filler material with a layer sandwiched in between two other silicone layers. This construction acts as a barrier to slow the diffusion of (spread) any gel filler materials through the shell. The Siltex textured shell consists of a smooth shell to which is bonded an additional layer of silicone with a textured pattern imprinted into its surface. The implants will be available in sizes 100cc through 800ccs.
Your plastic surgeon will discuss these implants with you and explain why a particular implant my be best suited for you.


If any problems or complications occur during the study, you may be asked or with to obtain second opinions. You have the right to consult a physician of your choice.


You will talk about your procedure and participation in this Study with your doctor, in advance, and you should take sufficient time to think about your participation. You should check with your insurance company prior to the operation, as the surgery may affect your coverage.

Your participation in this study will be for a period of 10 years. You will be seen at 6 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 years. It is very important that you come back for all postoperative visits, as the information obtained from those exams is extremely important in the study of these devices.

For patients who have undergone breast implantation either as a cosmetic or a reconstructive procedure, health insurance premiums may increase, coverage may be dropped, and/or future coverage may be denied. Treatment of complications may not be covered as well. Check with your insurance company regarding these coverage issues.


If you agree to be in this research study, you will first have to be examined by your doctor to determine if you are a good candidate and if you are eligible. This screening may involve referral to other specialists. Follow-up visits to other specialists may also be required. During this visit, a medical history and physical examination will be completed. Your doctor will ask you questions about any rheumatology diseases and symptoms you might have and you will be asked to fill out quality of life questionnaires.

Rheumatology Assessment

Your doctor will administer a rheumatic disease diagnosis questionnaire prior to your surgery. This is required to provide information about the possible relationship breast implants may have with connective tissue disorders, arthritis, and rheumatic conditions. This questionnaire will be administered again at the 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 year visits after your surgery.

Quality of Life Questionnaires

You will be asked to complete the Quality of Life questionnaires prior to your surgery. These are "paper and pencil" questionnaires, which will take approximately 30 minutes to complete. These are required to measure how you feel about your body before and after your breast implant procedure and are a very important part of your research. You will be asked to complete these questionnaires again at the 1, 2, 4, 6, 8, and 10 year visits after your surgery.

Description of the Operation

A surgeon using accepted standards of practice will perform your operation. The operation may be performed in a physician's office, a hospital operating room, or in an outpatient surgical center. Hospitalization may or may not be required. Your doctor will explain the particular type of implant that will be used, how and where it will be placed and the type of anesthesia to be used. He/she will also give you an overall description of the operation.

You may require surgery to correct any complications that may arise or revisions such as change in implant size that you may request.

Follow-up Visits

After your surgery, you will be asked to make visits at the following time periods after the surgery: 6 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 years. each visit will take about 60 minutes. Your doctor will perform an evaluation of the status of the implant and you will be examined for the presence of any post-surgical complications.

You are making a commitment to continue in the study for the duration and to complete all of these follow-up visits. The information obtained from these visits is important in the study of these breast implants. If you move, arrangements will be made with your doctor for follow-up visits with another doctor in your area.

Magnetic Resonance Imaging (MRI)

Breast implants may not last a lifetime. The shell may rupture due to wear and tear, or direct injury. Rupture should be suspected if there is a change in character of the implant such as a new, persistent burning sensation on one side or a change in softness, texture or shape of the implant, and may be difficult to diagnose without surgical exploration or a magnetic resonance imaging (MRI) scan. This type of examination produces a picture of your breasts without using x-rays and is commonly used in the x-ray departments of most hospitals to detect problems in bones, lungs, and all other areas of the body.

The MRI scan has been determined to be the best way to find out if your implant has ruptured without performing surgery. In order to detect a "silent rupture" (a rupture without any symptoms or visible changes), you may be in a subset of patients who will undergo an MRI scan at 1, 2, 4, 6, 8, and 10 years after your surgery. If you do, you will have to lay on your stomach with your breast in a special holder. You will then be placed in the machine, which may be open or may be like going into a tunnel. Some patients experience an uneasiness at being in a closed space. While the machine is taking images of your breast, it will make a noise. In order to have an MRI scan, you must not have any implanted metal or metal devices in your body, or a history of claustrophobia. The procedure should take about an hour. Mentor will pay for the MRI scans.

Any patient who is suspected of having a ruptured implant while in the study will be examined by her doctor and undergo an MRI scan to see if her implants are ruptured. Mentor will pay for these MRI scans.


As a participant in this study you will be asked to participate in the breast implant patient registry. This will allow Mentor to notify you, if necessary, of any new information about the safety of your silicone-filled breast implant(s). Every effort will be made to keep the information in the registry confidential and that information will only be provided to the FDA upon their request. However, under certain circumstances, Congress has the right to get clinical data from the FDA or a court could order disclosure of certain information that could include your clinical study records.

Your doctor will provide you with the identification information, which pertains to your implant(s) after your surgery. This will let you know what type of implant you have. This should be kept with your important papers for future reference. You should also remain in contact with your doctor to get current important information or, if you leave your doctor, you should leave a forwarding address.


Breast augmentation surgery is elective surgery designed to improve your appearance. Women with breast cancer have reported that breast reconstruction with mammary implants has aided in their recovery from breast cancer and has reduced emotional stress by helping to return their body to a more natural appearance.

You may benefit other women by providing information about possi le health problems associated with breast implants and to help demonstrate the safety and effectiveness of the device. There are no additional benefits to you beyond receiving this implant.


Breast surgery requires an incision. As with any surgical procedure, there are risks such as:

Infection: (severe infection on rare occasions results in Toxic Shock Syndrome or TSS). An infection can result from any surgery and produce swelling, tenderness, pain and fever. Almost all infections appear within a few days of the operation but may appear at any time after your surgery. If you get a serious infection, which doesn't go away with antibiotics, your implant may have to be removed.

Hematoma Formation: a collection of blood in the surgical area.

Seroma: (fluid accumulation around the implant which may or may not require removal). Your body will absorb both areas of fluid accumulation (seromas) and small hematomas, but large ones may have to be drained surgically to permit proper healing. Surgical techniques, under most circumstances, can minimize though not eliminate them.
Scarring: Any incision in the skin will leave a scar that is permanent. While your surgeon will use plastic surgical techniques to make this as inconspicuous as possible, some patients have a skin quality that results in more conspicuous scars no matter how the incision is repaired.

Anesthetics: There are risks from anesthetics as well.


Breast Implants have certain specific risks and complications which may include:

Capsular Contracture: The normal healing scar membrane that forms around the implant can, in some women, tighten and squeeze the implant. This can cause the implant to feel firm. This firmness can range from slight to quite hard and the firmest ones can cause varying degrees of discomfort or pain. In addition to the firmness, capsular contracture can result in a misshapen breast, visible surface wrinkling and/or displacement of the implant. Detection of breast cancer by mammography may also be more difficult.

If you wish to have this contracture softened, the scar tissue can be released or removed by making an incision into the breast during an operation called an Open Capsulotomy.

Your surgeon may recommend a technique called a closed capsulotomy in which he/she will apply forceful external pressure to the breasts to "break up" the scar tissue. Mentor does not recommend this technique because it could result in several complications such as breakage of the implant, bleeding, displacement of the implant resulting in asymmetry or distortion.

Your surgeon will explain the possible complications, as well as help you determine the best method for correcting capsular contracture.

Calcification of the capsule surrounding the implant can also occur. This can contribute to the hardening of the tissue and may be painful. Sometimes, it may be necessary to remove the implant and/or the calcified capsule.

Rupture of the Implant: Breast implants may not last your lifetime. The shell of a silicone gel implant can break due to injury or normal wear and tear over time, releasing the silicone gel filling. The Mentor Round Low-Bleed Silicone Gel-filled Mammary Prostheses can break without any noticeable symptoms. Some women have reported a burning sensation or a change in the feel and shape of the breasts. You should see your doctor if you notice these symptoms, or if you think for any reason that your implant might be broken. The rate at which silicone gel-filled implants rupture is uncertain. However, using different methods of detection, published studies suggest a rupture rate between 5 and 51 percent. While no guaranteed method to detect breakage now exists without surgically opening the pocket containing the implant, magnetic resonance imaging (MRI) and physical examination can usually help your doctor make the diagnosis. Implants that rupture usually require removal and replacement.

Causes of implant rupture include, but are not limited to: damage from surgical instruments, intraoperative or postoperative trauma, excesses stresses that may occur during daily routines such as vigorous exercise, athletics, routine manual massage and intimate physical contact, mechanical damage prior to or during surgery, closed capsulotomy, and capsular contracture.

A silicone gel-filled implant may rupture but stay within the fibrous scar envelope the body has made around the implant. Silicone gel which escapes the fibrotic capsule surrounding the implant may spread away from the breast. The free silicone may cause lumps called granulomas to form in the breast or other tissues where silicone has migrated to, such as the chest wall, armpit, arm, or abdomen.

Addendum from Mentor: Breast implants are not lifetime devices and cannot be expected to last forever. Some implants deflate or rupture in the first few months after being implanted and some deflate after several years; others are intact 10 or more years after the surgery.

Gel Bleed: Silicone gel is made up of a sponge like mesh filled with silicone in oil form. This oil is used in many medical products such as syringes, pills, and anti-gas medications such as Mylanta. It is known that some very small amounts of the oil part of the gel "bleeds" through the implant's covering or envelope. Although most of this stays in the implant pocket or is trapped in the surrounding scar, minute amounts of this silicone could possibly travel (migrate) to different parts of the body.

Silicone oil has not been demonstrated to cause cancer or other illness.

Changes in Nipple and Breast Sensation / Breast Pain: Any surgery on the breast, including a biopsy or breast implant surgery, can result in the breast and/or nipple being oversensitive or undersensitive on one or both sides. This change can vary in degree and may be temporary or permanent. It may affect comfort while nursing or sexual response.

Most women undergoing augmentation or reconstruction with a mammary prosthesis will experience some breast and/or chest pain postoperatively. While this pain normally subsides in most women as they heal after surgery, it can become a chronic problem in other women.

Chronic pain can be associated with hematoma, migration, infection, and implants that are too large, or capsular contracture. Sudden severe pain may be associated with implant rupture.

Interference with Mammography in Detection of Cancer: An implant may interfere with the detection of early breast cancer because it may "hide" suspicious lesions in the breast during an x-ray examination. It is especially important for women who are at high risk of developing breast cancer to consider this before having implants. The earlier cancer is detected, the better a chance for a cure.

Regular self-examination is very important for all women but especially if you have implants. You are urged to contact the American Cancer Society for literature and instructions on the early detection of cancer.

Since the breast is compressed during mammography, it is possible, but rare, for an implant to rupture. These problems can be reduced, but not eliminated, by asking if the personnel at the facility are experienced in performing mammography on women with implants. Before the mammography exam, you should tell the technologist that you have implants. The technologist should take special care when compressing the breast to avoid rupture. Also, an experienced technologist should know how to push the implant away from the breast tissue to get the best possible views of the tissue. Even when this special technique is used, some breast tissue may be missed in the x-ray. More x-ray views are necessary with these special techniques; therefore, women with breast implants will receive more radiation. However, the benefit of the mammogram in finding cancer outweighs the risk of the additional x-rays.

Calcium Deposits: Small spots of calcium in the breast are often found in any breast and can be seen on x-rays (mammography). These deposits may not occur in breasts with implants and may not appear for years after the implant surgery. They are benign (non-cancerous) and cause no problems but must be differentiated from the calcium that is often seen in breast cancers. An expert radiologist can usually tell a benign (non-cancerous) calcium spot from a malignant one but occasionally a biopsy may be necessary to make this distinction. Some patients may develop a thin layer of calcium in the scar capsule that surrounds the implant. This is almost always associated with capsular contracture but otherwise causes no known problem.

Delayed Wound Healing: In some cases, the incision site fails to heal normally.

Extrusion: Unstable or compromised tissue covering and/or interruption of wound healing may result in extrusion, which is when the breast implant comes through the skin.

Necrosis: Necrosis is the formation of dead tissue around the implant. This may prevent wound healing and require surgical correction and/or implant removal. Permanent scar deformity may occur following necrosis. Factors associated with increased necrosis include infection, use of steroids in the surgical pocket, smoking, chemotherapy/radiation, and excessive heat or cold therapy.

Breast Tissue Atrophy / Chest Wall Deformity: The pressure of the breast implant may cause the breast tissue to thin and shrink. This can occur while implants are still in place or following implant removal without replacement.

Dissatisfaction with Cosmetic Results: You may not be satisfied with the appearance of your breasts after implants. The surgeon has only limited control over the final shape which is determined by how your chest, your breast, and the implant all fit together. Incorrect implant size, excessive scarring, and misplacement of implants may interfere with satisfactory appearance. Asymmetry (unequal breast size or shape) may not be totally corrected even by different sized implants. The implante

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