Breast Implant Information
Choosing a type of breast implant for breast augmentation can be very confusing. The type of implant is chosen by the patient after studying the types and styles of implants. The information below can assist in making the decision. There are advantages and disadvantages to all types of breast implants and understanding these factors is important before choosing an implant type.
Breast implants were first used in 1962 to enhance the shape and size of breasts. The implant used at that time was a silicone gel implant. At the time of the first breast augmentation, very little was known about breast implant technology (device manufacture), and very little was known about the technical aspects of the breast augmentation procedure.
In the first breast implants, silicone was used as a filler (material inside the implant). Silicone was used because it was the correct consistency (about the same softness as breasts) and because was thought to be inert (not eliciting any severe harmful reaction from the tissue) when in contact with living tissue. Silicone implants have gone through several iterations since they were first used in 1962 by Dr. Thomas Cronin.
Research since 1962 has improved the understanding of this biomaterial which has been incorporated into implant manufacture. The improvements in silicone implants include both changes in the shell of the implant (the outer covering) and changes in the silicone filler (the semi-solid inside the breast implant shell).
A problem with the early silicone breast implants was the leakage of free silicone. This has been termed “gel bleed”. Silicone can also escape the implant by rupture of the shell. A large percentage of early liquid silicone breast implants had rupture of the shell. When this occurs, the tissue surrounding the breast implant is potentially exposed to the entire contents inside the shell.
With the older type of silicone implants, the silicone was more “liquid” and had a tendency to cause a granulomatous reaction (so not completely inert). This is an inflammatory reaction that results in the infiltration of a specialized cell known as a histiocyte. The resulting mass is termed a “silicone granuloma”.
When silicone leaks into the tissue around the breast implant, it is not thought to cause general (systemic) disease. This has been studied independently by many researchers and no evidence has been found to suggest that silicone breast implants cause systemic disease.
Collagen vascular diseases (connective tissue diseases) have been specifically studied and no relationship between silicone breast implants and that disease entity has been established. Silicone granulomas and free silicone in the breast could cause in the diagnosis of breast cancer to be more difficult. Silicone granulomas and free silicone could make discovery of a breast mass more difficult by physical exam, and could also make radiology screening tools such as mammograms and ultrasound.
The migration of free silicone to other parts of the body could cause other problems such as nerve compression. Because of these problems, efforts were made to prevent silicone leakage and shell rupture.
Breast implant technology has been improved dramatically over the last 30 years. Silicone implants used 30 years ago were filled with liquid silicone. The silicone inside the implant had a tendency to “bleed” through the shell. This resulted in free liquid silicone in and around the breast gland.
The free liquid silicone inside the breast and in the armpit had the potential to make screening and diagnostic breast imaging more difficult. This was a major concern because the free silicone could potentially delay the diagnosis of breast cancer and could also interfere with the treatment of breast cancer. The free silicone could also migrate to areas far distant from the breast. Although this did not usually cause problems, the potential for problems did exist.
Saline (salt water) breast implants were first used in 1965, several years after silicone implants were first used for augmentation. Saline breast implants were invented to allow a shorter skin incision as compared to silicone implants. This is because saline implants they are filled after placement in the pocket. There are many other advantages to saline breast implants explained later in this section.
One problem with saline breast implants just after they were invented was deflation or leaking. This was usually a result of a problem with the shell (outer covering) leaking or a problem with the valve (part that allow filling of the implant) leaking. Because the implant is filled with saline, which is salt water, leaking of the implant into breast pocket is generally not thought to cause problems. The saline (salt water) is absorbed and excreted.
Improvements in the manufacturing process have improved the integrity of the breast implant shells. Improvements have also been made with the valves in breast implants. Both of these improvements have decreased the rate of breast implant deflation.
Before choosing and implant filler (saline or silicone), the patient should understand all the advantages and disadvantages of the fillers and the shell design (shape and texture). The breast implant type should be chosen based on comparison on all parameters and can vary from patient to patient.
Recommendation of a filler type by a patient with breast implants may be a consideration, but should not be the sole factor when choosing an implant type. A patient’s satisfaction with a particular type of breast implant does not mean it is ideal for every patient. Instead, the implant filler type should be chosen after a consultation with a Plastic surgeon, study of written information, and comparison of the advantages and disadvantages of filler types.
There is no urgency in choosing an implant filler type before the consultation. The consultation is the time to gather information and ask questions and the decision made after careful consideration. The choice should be made after careful study and the opportunity to discuss the topic at length with a qualified Plastic surgeon.
Research over the last thirty years has helped understand how the human body reacts to breast implants. Breast implants introduce a foreign material into the body. The reaction of the body to any “inert” smooth material is similar. A smooth scar forms around the foreign material. This scar is referred to as a “capsule”.
This tissue reaction is seen with many medical devices including breast implants. This reaction is also seen with shunts, artificial joints (knee, hip), heart pacemakers, and drug delivery devices (for diabetes). The breast implant shell is “recognized” as a foreign material by the body tissues. Although it is considered an “inert” biomaterial, the silicone shell does cause a reaction in the body. The “capsule” that is formed around the implant acts a protective layer between the implant and the rest of the body.
The capsule is living reactive tissue that contains blood vessels and other anatomical structures. All breast implants are surrounded a “capsule” to some degree. The breast “capsules” vary in structure depending upon the surface characteristics of the breast implant shell (smooth silicone, textured silicone, polyurethane foam). In most circumstances the breast implant “capsule” does not cause any problems and is just considered part of the normal healing process.
Scar tissue that forms around the breast implant is termed the breast “capsule”. This occurs to some degree with every breast implant. If the scar tissue is excessive and shrinks, this can cause firmness of the breast. When this is problematic it is referred to as “capsular contracture”. Capsular contracture can cause discomfort in the breast if severe. The term “contracture” means that the scar tissue around the implant has become excessively tight.
Severe capsular contractures can cause the shape of the breast to distort and appear abnormal (more below). The capsules around the breast can become calcified in the most severe cases. This is commonly observed with first generation silicone breast implants when they are removed years later.
In addition to causing pain around the breast implant, problematic breast capsules can also make breast imaging (mammograms, magnetic resonance imaging, and ultrasound) more challenging, especially when they are severely calcified.
Excessive scar tissue can change the appearance of the breast. When a severe capsule occurs, the breast tends to take on a more spherical shape rather than the normal teardrop shape. This is particularly true in patients that have thin breast tissue (extremely small breasts).
Thin breast tissue can be generally be defined as a breast plate that is less than 2 centimeters thick on the “pinch test”. The breast thickness can be measured with a gauge to accurately determine the amount of native breast tissue. The surface characteristics of the breast implant in part determine the characteristics of the breast capsule.
When the capsules from different types of implant shells are examined, they show differences in both gross exam (what you see with the naked eye) and microscopically (what you see under the microscope).
There are two different types of visible implant irregularities associated with breast implants. These surface irregularities can occur uniquely and occur together. One type of irregularity is wrinkling. Wrinkling of the breast prosthesis is easier to observe and feel in patients with very thin breast tissue.
In this circumstance, the irregularity can be visible especially in tangential light. A wrinkle in a breast implant can be defined as a gentle change in contour that creates shallow “hills and valleys” that can be seen and felt in thin patients. Breast implant wrinkles can be observed in both saline and silicone breast implants.
The second type of irregularity is a fold in the breast implant. A fold in a breast implant could be considered as a wrinkle taken to an extreme degree. Folds in breast implants can occur in both saline and silicone implants. Both wrinkles and folds can be observed by the surgeon when a patient has a replacement of breast implants.
In some circumstances deep folds are seen during surgeries that were not obvious during the pre-operative physical exam. In some patients wrinkles and fold in the breast implants can be observed and felt during the pre-operative exam. Wrinkles are unlikely to cause loss of integrity of the breast implant shell.
Folds in the implant, at least theoretically, could cause problems with the implant shell as a result of friction between the two opposing sides of the shell. The friction created from the contact between could theoretically cause weakening of the shell and implant deflation.
There may be a difference in the rate of breast implant wrinkling between different types of breast implant shells. The breast implant shells are either smooth, or textured (rough surface). The rough surface breast implants (textured) have been observed to wrinkle more than the smooth shell breast implants.
There many factors other than the breast implant shell characteristics that can affect wrinkling. One important factor is breast implant fill volume (how much saline is placed in the implant). If a saline breast implant is “under filled” then it may be more likely to wrinkle. In this context, “under filled” means the implant is filled with less saline than the maximum recommended range.
Some information shows that silicone breast implants are less likely to wrinkle than saline implants, but both can wrinkle. Differences in breast capsule structure would partially explain different capsule contracture rates for the different types of breast implant shells.
In general, textured breast implant shells have lower capsular contracture rate than smooth shell implants. Other information indicates that silicone breast implants wrinkle just like saline breast implants. As with capsular contracture, there are many factors that may cause a breast implant to wrinkle other than the filling material.
In addition to shrinkage of the breast capsule, muscular action in under the muscle breast implants may contribute to wrinkling. Severe capsular contracture can cause breast implant wrinkling which is commonly observed by surgeons when replacing breast implants. As with capsular contracture, breast implant wrinkling can be more obvious in patients with thin breast tissue.
If a patient has very thick breast tissue, the implant may become wrinkled but the breast tissue prevents it from being noticeable. The fact is, both silicone breast implants and saline breast implants can wrinkle.
Factors affecting breast implant wrinkling are complex, and include capsule formation, variations in saline fill volume, normal variation in patient anatomy (breast gland thickness), surgical techniques, and bias by the examiner (surgeon). It is possible that most breast implants wrinkle to some degree if present long enough.
One important factor is the amount of breast tissue present, because if the breast tissue is of significant thickness, then wrinkling of the implant may not be detectable. It is very difficult to know exactly what percentage of implants wrinkle and/or fold.
Breast implant wrinkling is not the same issue as implant palpability. In patients that are very thin, the implant may be palpable, but not wrinkled. Breast implant palpability is a very challenging problem to remedy in very thin patients.
Another problem that can occur with breast implants is folding. This is different from wrinkling. A fold in an implant can be thought of as a severe wrinkle. In this circumstance, the implant surface is deformed to the degree that the exterior surface is juxtaposed. This means that the implant can “rub against itself” as the implant moves. This could theoretically weaken the shell causing failure of the implant.
Folding of the breast implant could also cause an appearance problem. As with implant wrinkling, this would be more obvious in a patient with this breast tissue. Breast implants can fold in some patients. When this occurs the fold may or may not be detectable by physical exam. Folded breast implants are common observed at the time of replacement (breast implants have been in place for some time).
Breast implant capsules are graded by severity; the higher the classification number, the more severe the capsule. The Baker Breast Capsular Contracture Scale is a system used to determine the severity of breast implant capsules. The classification system is somewhat subjective because it is based on the opinion of the examining physician, but it is still helpful in describing a physical condition.
The exact causes of problematic breast capsule contracture are not exactly known. There are many theories as to the cause of contracture, and it is likely that there is not one single cause, but many causes working at the same time. One theory concerning the cause of breast implant capsule contracture is an inflammatory process. This process could be subclinical, which means that the patient is not aware this process is occurring.
The inflammation is thought to be related to a small number of bacteria surrounding the implant that causes inflammation, but does not cause a clinical infection. There are other theories regarding the genesis of problematic breast capsules in addition to the aforementioned.
The problem of breast capsule contracture has existed since the beginning of the breast augmentation procedure. It is likely that the etiology of problematic breast capsules is multifactorial, meaning there can be multiple causes that interact. In addition there may individual (genetic) factors that influence the formation of problematic breast capsules. Plastic surgery research has been done to determine how to prevent and treat this problem.
The simplest treatment is “breast massage”. Theoretically, regular breast massage would keep the potential volume (size) of the breast pocket larger than the implant which would the breast and breast implant to remain soft. In most circumstances, it not the implant that become firm or hard, it is the capsule around the implant.
There are circumstances where the implant itself becomes hard but this situation is much less common. This could occur when the shell of the implant becomes calcified (contains calcium) and when this is occurs it is typically in an implant that has been in place for many years. In these circumstances it is not uncommon to find the breast capsule is calcified in addition to the shell of the implant.
The breast message may be more effective in patients with smooth shell breast implants (as compared to textured implants) because to implant can slide inside the pocket which stretches the capsule. Breast massage is generally not recommended as a treatment for severe breast implant contracture for a number of reasons. Breast massage is usually recommended as a preventive measure (prevention of breast implant capsule shrinkage or contracture).
About 30 years ago, steroids were injected into breast implants in hopes of preventing problematic breast capsule contracture. This was not found to be a good preventive treatment and was abandoned. Antibiotics were injected into the breast implants as a preventive measure. This was not found to be effective and was abandoned.
There was also concern that the shell could be degraded by exogenous compounds (antibiotics). Special texturing using polyurethane was also use in hopes of preventing capsule formation. This was abandoned in part over concerns of the possible carcinogenic effects of degraded polyurethane. In addition, removal or removal/replacement of the implants could be technically challenging.
Alteration of the breast pockets has also been used in part to solve the capsular contracture problem. Breast implants have been placed sub-glandular, sub-muscular, partially sub-muscular, sub-fascial, and partially sub-fascial in an effort to improve the results. The scientific study of this problem is challenging as a result of all the variables that exist in its study.
Variables include but are not limited to differences in surgical technique among surgeons performing breast augmentation, variable time in patient follow up, patients lost in follow up, individual differences in patient response, differences in breast implant fillers, differences in breast implant shells, compliance or non-compliance by patients, and variation in evaluation of research parameters. While research on this topic is not perfect, it is helpful in making decisions and modifying protocols for breast augmentation.
It is most likely that there are many causes of problematic breast capsule contracture. Other theories regarding the etiology of breast implant capsule contracture include subclinical bleeding (small amount of blood around the implant) which probably occurs in many patients.
Atypical immune response to the implants, tendency of the patient to form problematic scars and failure of the patient to follow post-operative instructions may also be a factor. For example, the patient may fail to take antibiotics as instructed which could increase the risk of infection. If problematic capsular contracture is caused by more than one factor, it is also likely that these factors interrelate and work cumulatively.
As an example, if there is bleeding around the breast implant after surgery then this could create an environment where bacteria could flourish ultimately resulting in a subclinical infection. Position of the breast implant (above the muscle, below the muscle, or partially below the muscle) may also affect the probability of getting a problematic capsular contracture. Some information suggests that breast implants placed below the muscle are less likely to develop a problematic capsular contracture.
If this is accurate, this could be a result of a more robust blood supply next to the implant, the muscular action (message) on the implant, or a combination of these factors. A capsular contracture can occur in any patient with any technique or any type of implant, so there is not a pathway to prevent this in 100% of patients.
With severe breast capsule contracture, the patient may request surgical treatment to relieve the problem. There are two basic surgical treatments for severe symptomatic breast capsule contracture. A capsulotomy (-otomy means to make an incision or cut into) is the simple opening of the capsule. This procedure relieves the pressure around the implant by creating more potential volume in the breast pocket. This makes the breast and breast implant feel softer. The second procedure is a capsulotomy/capsulectomy.
This procedure surgically removes part of the breast capsule around the breast implant. This procedure also increases the volume of the breast pocket around the breast implant which makes the breast and breast implant feel softer. When a capsulectomy is performed the tissue removed is submitted for pathological examination. Finding unexpected significant pathology (cancer) in the removed capsule is rare.
Historically, saline breast implants have been thought to cause fewer problems with severe breast capsule contracture than silicone implants. This information may be irrelevant because it is based old breast implant technology. It takes many years and many patients to study any topic in healthcare. There are many other factors that could compromise the study of breast implant capsules.
Baker Breast Capsule Classification
|Grade 1||Soft breast in which the implant and capsule are not noticeable|
|Grade 2||Minimally palpable implant and capsule|
|Grade 3||Firm breast and capsule in which the implant can be palpated and distortion might be seen|
|Grade 4||Firm, painful, and tender breast with significant visible breast distortion|
The ability to adjust the size (volume) of breast implants at the time of surgery is a great advantage. Saline breast implant volume can be adjusted to a predetermined volume at the time of surgery because they are filled by the surgeon at the time if surgery. The general breast implant size in cc’s the patient desires is always determined before the time of surgery, it is a great advantage to be able to adjust the size at the time of surgery to correct small asymmetries. If a patient has significant asymmetry before breast implant surgery, saline breast implants may be the best choice.
Conversely, silicone implants cannot be adjusted at the time of surgery because they are pre-filled during the manufacturing process. This is a distinct advantage of saline breast implants over silicone breast implants. Silicone breast implants are filled at specific interval volumes. If the specific volume of the breast implant desired is not available in the silicone style, then a saline breast implant may be a better choice.
Saline breast implants are filled after they have been placed in the breast pocket (inside the breast). This means that when saline breast implants are placed inside the breast they can be at very small (low volume). As result, a small incision can be used to place the implant inside the breast.
On the other hand, because silicone breast implants are full at the time they are placed inside the breast, a much longer incision is required. In general, the incision length for saline breast implants is shorter than the incision length for silicone breast implants.
Breast implant shell (covering or outer part of the implant) can rupture. This means that the shell of the implant allows the filler (saline or silicone) to escape. The rupture of breast implants is not thought to cause any systemic problems (infection, collagen vascular disease), meaning general health problems.
If a patient has saline implants, this means they are filled with salt water. If the salt water leaks out of the breast implant it is absorbed by the body without consequence. It is as if the patient drank salt water. It is believed that saline escaping from saline breast implants causes no general health problems. It is possible that the saline inside the implant contained bacteria that could cause an infection after breast implant rupture, but if this occurs, it is a rare event.
Silicone breast implants can also rupture which allows free silicone to be exposed to the breast tissue and surrounding tissue. Free silicone could cause problems around the breast and anywhere else the silicone migrates. Silicone is biologically “inert”. This means that it does not cause a severe tissue reaction in and of itself. The problem that can occur is that silicone may create a situation where the body’s normal defense systems cannot fight bacteria which could result in an infection.
Any foreign body can potentially decrease the body’s immune response and silicone is not different. In summary, silicone itself does not cause a problematic tissue reaction or infection, but it can potentially create a milieu (environment) where an infection could occur.
Another concern about breast implants, and mostly about silicone implants, has been the concern regarding collagen vascular diseases. These are a group of diseases that are considered autoimmune diseases. This group of diseases occurs when the body “attacks itself”. The most commonly occurring and most commonly known collagen vascular disease is rheumatoid arthritis.
It has been estimated that at least 1 in 5 people in the United States have this disease. Other types of this disease include lupus, scleroderma, polymyositis, and dermatomyositis. Many scientific reports have been published and they have not shown any link between breast implants and collagen vascular disease.
Diagnosing the rupture of saline breast implants can usually be done clinically (by physical exam). When saline breast implants rupture the breast decreased in size. There are two ways that saline breast implant can present.
One is a complete breast implant deflation. When this occurs, the saline breast implant has (virtually) no saline in it. In this circumstance, the clinical diagnosis is usually obvious because one breast is significantly smaller than the other (obvious asymmetry).
The second situation that can occur is a partial breast implant deflation. This type of deflation is more difficult to diagnose because in this case there is some saline left inside the implant. The physical exam with a partial saline breast implant may show only a slight difference in breast size.
Because all breasts in the same patient have some degree of asymmetry before and after breast augmentation, diagnosing a partial saline breast implant deflation can be challenging. When a partial breast implant deflation is expected it is prudent
Silicone breast implant ruptures are much more difficult to diagnose compared to silicone implants. Because the escaped silicone is not absorbed by the body (like saline after saline breast implant rupture) after shell rupture, the breast may stay the same size and shape even when the implant is ruptured. This has been termed a “silent rupture”.
Because the breast size and shape may not change with silicone breast implant rupture, accurate clinical diagnosis without other studies is may be impossible. The FDA (Food and Drug Administration) recommends that all patients with silicone breast implants get an MRI every 2 years to check for silicone breast implant rupture.
MRI studies are very expensive and some insurance companies will not pay for this study because the breast implants were placed for cosmetic reasons. As a result, the cost for the MRI studies will be very expensive over a long period of time.
This reason alone may be a factor in choosing saline breast implants because MRI is not recommended with these (saline) devices. It is very important that the patient is informed of this FDA recommendation before choosing a type of breast implant.
The new “5th generation” silicone breast implants are filled with “cohesive gel”. Because the silicone inside the breast implants is cohesive (maintains shape), theoretically the silicone will not migrate if the implant ruptures. The new silicone implants, sometimes referred to as “gummy bear” implants, are currently being studied.
Because there are so many variables occurring at the same time, it is difficult to make firm predictions for an individual patient. In some circumstances, information on breast implants has been based on opinion, which is the least accurate type of scientific information.
A significant percentage of patients will undergo surgical revision after getting breast implants at some time. There are many reasons patient seek breast implant revision including change in breast implant size (smaller or larger), breast ptosis (sagging), breast shape, and implant deflation. Revision surgery is usually easier with saline breast implants as compared to older generation silicone implants. This is another advantage of saline breast implants.
The cost of breast implants can be a consideration for some patients. A significant part of the breast augmentation procedure is the cost of the implants themselves. Silicone breast implants are much more expensive than saline breast implants which makes the total cost of the procedure significantly higher.
The desirability of more or less supple implants is based on nothing other than opinion or preference. Some Plastic surgeons recommend silicone breast implants because they think these implants feel more “natural”. This recommendation is based solely on opinion. Some Plastic surgeons recommend saline breast implants because they think these implants feel more “natural” or “youthful”. This recommendation is based solely on opinion.
The breast tissue (includes breast gland and other tissues in the breast) does not remain the same throughout life. As aging progresses, the breast gland typically atrophies (gets smaller). This can be accelerated by pregnancy and breast feeding. As aging progresses, there may be an increase in fat in the breast. These natural changes in the breast affect the suppleness of the breast. As patients age, the breast will typically become softer (more supple). This is an individual characteristic that varies from patient to patient but generally holds true.
An 18 year old patient with a highly glandular breast will feel very different than a 65 year old patient’s breast that is mostly composed of fat. The desired suppleness of the breast can be translated to the choice of breast implant filler. If a suppler breast is desired, which would be comparable to a fatty breast, then a silicone breast implant may be desired.
If a more firm breast is desired, which would be comparable to a youthful glandular breast, then a saline breast implant may be desired. Ultimately it is the patient’s choice as to which implant filler is chosen.
Breast implants have different types of shells (outer covering of the implant). The shells of breast implants have been improved over the years as a result of research. There is a balance between having the shell too thin in which case the risk of rupture may be increased, and having a shell that is so thick that it is non-compliant (too stiff). The surface characteristics of breast implant shells are either smooth or textured (rough). Both shell surface types have advantages and disadvantages.
The choice of the implant type, including the type of filler of the implant, the choice is made by the patient. While the Plastic surgeon provides information and advice to the patient based on the patient’s individual situation, the Plastic surgeon does not make the final decision.
The main reason (and possibly the only reason) for choosing silicone breast implants is the “feel” of the implant, meaning silicone tends to have a preferred degree of suppleness. Silicone breast implants may feel more supple than silicone breast implants, but this is highly dependent on the fill volume of the saline breast implants.
Comparison of Saline breast implants vs. fifth generation Silicone breast implants
|Saline breast implants||Silicone breast implants|
|incision site smaller||incision site larger|
|can adjustable size||cannot adjust size|
|firm fully filled or overfilled||softer at filled volume|
|implant wrinkling possible||implant wrinkling possible|
|cost higher||cost lower|
|MRI not needed||MRI needed (FDA)|
|product use longer||product use shorter|