Common Questions

These terms are confusing because they are all marketing terms. None is scientific and none is defined. (Actually there is a definition of cohesive, but no one really follows it.) Manufacturers want to use terms that distinguish their products; surgeons want to promote themselves as doing something unique; and the FDA watches over to be sure that false claims are not made. During the cohesive trials which lasted over a decade, surgeons who did not have access to them became frustrated and started to claim that their products were cohesive (when they really were not.) Gummy bear is obviously not a scientific term and since it isn’t, then there are no strict criteria for what gummy bear really means.

Each manufacturer uses their own system to grade cohesivity so it is impossible to compare between them – that is if doctors were even given access to those numbers. But manufacturers consider them trade secrets so objective comparisons cannot be made – only clinical impressions by the surgeon.

He is one of the only – and perhaps the only – surgeon in the United States to have participated in the studies of all of these types of implants. So he has experience with them all and has insights into the subtle differences between them.

The term gummy bear was coined by a CEO of a breast implant company in the early 2000’s. He joked that he was so busy that his lunches were gummy bears and Diet Coke. In a marketing meeting about breast implants with his staff, he bit into a gummy bear and remarked that it reminded him of the implants. It was soft but yet it could retain the shape of a bear. To Dr. Teitelbaum it denotes a soft implant that has a tendency to maintain its shape. But the term has no definition. Some plastic surgeons use it to describe less firm retaining shapes but Dr. Teitelbaum feel that is misleading.

About ten years ago, if a doctor said an implant was cohesive, it was understood he or she was referring either to the Allergan 410 or to the Mentor CPG. But those were available to just a few researchers in the United States. The public became interested in them. So doctors not using them started saying that all implants were cohesive. Understanding the cache of the term cohesive, one implant manufacturer advertised that all of its implants were cohesive. This created “cohesive confusion.” The upshot was that some plastic surgeons started referring to the Allergan 410 and the Mentor CPG breast implants as being “highly cohesive”.

Technically it is correct that all implants are cohesive. But the original use of the term referred to implants that were able to hold a shape. Today plastic surgeons may refer to those implants as highly cohesive.

Form stable implies that the implant has a shape and no matter what position it is put in it will maintain that shape. The Allergan 410 is the closest implant to form stable, but even it is a bit malleable – as it should be. Anything totally form stable would feel too hard.

The reason a round implant can look at all natural is that when a woman stands gravity transfers some of the fill from the upper part of the implant down to the lower part, imparting somewhat of an anatomical shape. If a round implant is made with a highly cohesive filler, it looks too round and unnatural. That is why cohesive implants are made in an anatomic shape.

They exist outside of the USA. They tend to look very round because there is no transfer of fill when a patient stands up so the upper pole remains bulgy. Some physicians refer to the Sientra round implant as being cohesive, but it can collapse much the same as the standard implants made by Allergan and Mentor.

There was an anatomically shaped implant in the 1980s that gave a great shape for a short while. The problem was that the gel was too much of a liquid, so it soon lost its shape, folded, broke, and leaked. The idea behind creating a cohesive implant was to help it maintain its shape, prevent folding, reduce the chance of breakage, and reduce the likelihood that gel could leak.

They were invented in the early 1990s with the 410 implant.

Maintaining a shape, preventing folds, longevity, and minimizing leaking.

In order to hold a shape and reduce the chance of leaking, they need to be firmer. That isn’t a problem in tighter, younger breasts. But they may feel firm to patients with softer and looser breasts. Anatomically shaped implants have a risk of rotation. If a round implant turns it doesn’t cause a problem. But if an anatomic rotates, the thin part from the top may go to the bottom and the thick part on the bottom could create a bulge on the top. This doesn’t happen often, but is something to consider.

Since cohesive implants have a less malleable shape, they need to be fit much more precisely to the dimensions of the breast than regular gel implants which are capable of conforming to a wide range of spaces. Using shaped implants requires more technical precision than using standard implants.

This was the very first of the highly cohesive implants. It has been a widely used implant worldwide since the early 1990s. It comes in 12 different shapes for any given volume, giving the surgeon a wide range of shapes to choose from to create the ideal shape for a patient’s breasts. It is probably the firmest of the implants, though the additional firmness is not very distinguishable once in the body from other cohesive implants. In Europe there is a version of it called the 410 Soft Touch, which is a softer version of it. But the trade-off with that is that it has less of an ability to maintain its shape. The 410 had been in clinical trials in the United States since 2001 and was FDA approved in 2012. The company that launched the implant was called McGhan, which was later bought by Inamed, which was then bought by Allergan. So each of those names has been associated with the 410. Dr. Teitelbaum used hundreds of 410 implants during its clinical trial in the United States. He also was videotaped using the implants, and this video is part of Allergan’s physician teaching course on the proper use of the 410. Dr. Teitelbaum was also a primary writer of Allergan’s 410 educational curriculum. Photos of his own 410 patients are prominently displayed in Allergan’s 410 marketing materials, so he is undoubtedly a well-recognized expert using these implants.

CPG stands for Contour Profile Gel. It is Mentor’s most cohesive anatomically shaped implant. It was designed after the 410. It seems to be slightly less cohesive. The CPG has similar shapes to the 410, but the dimensions are notably different. It is probably a matter of surgeon and patient preference as to which shape is best. Mentor makes three types of silicone: Cohesive I, Cohesive II, and Cohesive III, with I being the least cohesive and III being the most. The standard silicone implant in the USA is a Cohesive I. The CPG is a cohesive III. There are no Cohesive II implants available in the United States. Mentor refers to the silicone in Cohesive I and Cohesive II implants as “memorygel”, and refers to the silicone in the CPG as “memoryshape.” Dr. Teitelbaum has experience using the CPG on hundreds of patients as a participant in their pivotal United States clinical trial.

Sientra is the US distributor for Silimed implants, which are made in Brazil. After 22 years of only two US implant makers (Allergan and Mentor,) Sientra became the first new manufacturer approved by the FDA in March 2012. They make both round and anatomically shaped implants. Dr. Teitelbaum has used them for many years on their clinical trial in the United States. Their round implants feel softer than their anatomic implants, though they are technically the same implant.

MemoryGel is Mentor’s trademarked name for the silicone gel in its standard implants. MemoryShape is the trademarked name for the silicone in the CPG highly cohesive anatomic implant. The term MemoryGel is somewhat misleading because the implant does not behave with any memory: its shape is malleable and affected by gravity, not returning to any particular shape.

There are innumerable subjective distinctions Dr. Teitelbaum can make about these implants after using hundreds of them. They each have specific shapes and degrees of cohesivity that work in different situations. The problem is that the manufacturers will not release even to surgeons the critical parameters that enable a meaningful, scientific distinction between them. So we are left with nothing but surgeon impressions.

When the FDA approves an implant, the manufacturer is given a range of gel cohesivity for that approval. No one knows exactly how Sientra has done it, but the presumption is that the round implants are on the soft end and the shaped implants are on the firm end of the spectrum of their approval.

Which is Dr. Teitelbaum’s favorite gummy bear breast implant?

Even the most cohesive implants such as the 410 can ripple, but does so less often and to a lesser extent than standard silicone implants. But the most critical thing in rippling is not the implant; it is the thickness of the tissue over the implant and whether the breast envelope is filled by the implant.

Contrary to popular belief, cohesive implants can break. They appear to do so less often than regular silicone implants, but they are not unbreakable.

If the shell is disrupted, cohesive implants can leak. Their gel is much thicker than that of standard implants, so the gel tends to stay around the implants. But it is a misnomer that these implants cannot leak.

Cohesive implants can be a part of the solution to correct rippling. In some situations they do correct rippling. But rippling is mostly about the thickness of the coverage and whether the breast envelope is filled. Many patients and even plastic surgeons view cohesive implants as a panacea for rippling, and though they can be great, they are not a panacea.

Teardrop implants can rotate. But if the implant fits the tissue, and if the surgeon makes a pocket that fits the implant, then rotation should be a very infrequent problem. But it always remains a risk with anatomically shaped implants. It is a reason why shaped implants aren’t always a good choice for revisions. It is the pressure of fresh tissue on the implant that helps maintain its position, and in revisions that is often not the case.

Dr. Teitelbaum holds a patent on a device that uses specific patient tissues measurements to show a surgeon the ideal implant shape for that patient. Allergan has bought the technology and has a complete selector system for the 410 implant which it will make available to surgeons after the commercial launch of the 410.

Dr. Teitelbaum has used all three implants in clinical trials; he holds a patent on a cohesive implant sizing device; he has lectured and taught courses on it around the world; he was a consultant to one of the leading cohesive implant manufacturers and crafted much of its surgeon educational curriculum; he continues to be a thought leader and teacher to other surgeons on highly cohesive breast implants.