Gummy bear implants vs. Sientra implants

Sientra breast implants are made by the Brazilian company Silimed, which
started in Rio de Janiero in 1978 to import French breast implants into
Brazil for growing plastic surgery use in that country. In 1981 Silimed
began to manufacture its products in Brazil, in a small
laboratory compatible with the technical requirements of the time. One
year later, it already exported to other countries in Latin America and,
in the following years, expanded to foreign markets, with products
geared towards various specialties.

Silimed began construction of a new factory in 1985, which started
to operate in early 1989. In 2000, a second factory was built,
starting its activities in 2003. After 35 years in the market, Silimed
operates with two factories in Brazil and exports to all five
continents.In 1990, Silimed began manufacturing textured mammary
implants. In 1999, Silimed received 510K approval from the FDA (Food
and Drug Administration) in the USA for its textured and smooth silicone
elastomer implants. [this information from Silimed's own website
history of the company]On March 9, 2012, Silimed's Sientra
silicone gel mammary implants received FDA approval for sale in the USA.
Silimed is the first manufacturer
outside the USA whose silicone mammary implants, smooth and textured,
are approved in the USA. Furthermore, Silimed became the first
manufacturer in the world whose form-stable (teardrop shaped) textured
silicone gel implants were approved in the US market.
(Allergan--formerly Inamed--SUBSEQUENTLY received FDA approval for its
style 410 textured-surface shaped highly cohesive silicone gel implants,
the popularly-named "gummy bear" implants).But because
Sientra's high-strength, cohesive, form-stable (teardrop-shaped),
textured-surface implants were actually first to be FDA-approved in this
country (and because they have used that terminology in their website
information about their implants), many now call these "gummy bear"
implants as well. The terminology is therefore confusing, like calling
every facial tissue "Kleenex" when it might actually be a Puffs, or
every copy machine a Xerox, when it could be a Minolta. But you know
what I mean.Each of the 3 USA breast implant manufacturers has
shaped, textured-surface cohesive (or ultra-cohesive) implants, and each
manufacturer has their own patented or "trade secret" way of creating
the textured surface--the "proprietary" texturing method. McGhan (now
Allergan) implants use a lost-salt technique where salt crystals create
the high and low spots of the texture, designed to promote tissue
adherence and ingrowth. The salt is then washed away before implant
sterilization. This tissue adherence is not unlike Velcro, but is not
the "hook and fabric loop" structure that Velcro uses. This
texture mimicked the structural properties of polyurethane-covered
implants from 2 1/2 decades ago, where tissue ingrowth was shown to
reduce (or prevent) capsular contracture (CC). CC was much more common
at that time, since breast implants were usually placed ABOVE the muscle
and just below the breast tissue, where there was significant bacterial
contamination from the normal bacteria within the breast ducts. The
texturing was also thought to "break up" the unidirectional collagen
scar fibers that aligned themselves along a smooth-surface implant,
contracted, and formed CC. And it worked! CC rates diminished.Mentor
developed their own textured-surface implants (Siltex), and their
method of creating the surface texture was also proprietary (and
different). It was a stamping process that created a much more
finely-grained or almost "fuzzy" surface. My own experience with these
implants showed that tissue ingrowth and adherence did not happen with
this type or method of texturing, and years of experience with saline
textured-surface implants showed a higher leak rate.Sientra's
method of texturing implants leads to a texture much more similar to the
Allergan texture, but their technique is, again, proprietary, meaning
they have their own way of creating what they feel is a better texture
designed to promote adherence, ingrowth, CC reduction, and implant
rotation avoidance (since an upside-down teardrop-shaped implant or
sideways-positioned implant that was "stuck" there looks really wonky!We
know from other areas of bioengineering (such as rough-surface titanium
hip or other orthopedic implants) that human tissues do not adhere
equally to all man-made textured surfaces or materials. But we do know
that textured breast implants DO reduce CC, particularly when used above
the muscle. But since most plastic surgeons now place their breast
implants BELOW the muscles, and have learned that even without texture
this reduces CC significantly, the place for texture below the muscle is
less for prevention of CC than for prevention of rotation to an
abnormal position! We also know from X-ray studies of women with
smooth round breast implants and women with textured teardrop-shaped
implants, the round implants are actually teardrop-shaped when the woman
is standing, and indistinguishable from textured teardrop-shaped
implants. They looked identical! But when reclining, the smooth round
implants assumed a flatter round shape and dropped slightly to the side
of the chest, just like naturally large(r) breasts do, whereas the
teardrop-shaped implants did not move and poked straight up in an
unnatural still-teardrop shape, making these so-called "anatomic"
implants LESS anatomic than the smooth round ones.Sientra's website uses the term "gummy bear" implants, and even though "gummy bear" is not medical terminology, Sientra's marketing people are clever, and have chosen to use this popular lay term in its promotional materials. But Allergan's stylee 410 implants were actually the first ones to be termed the "gummy bear" implants, long before Sientra implants were FDA approved for use in the USA (March 9, 2012). However, Allergan did not received FDA approval for their stye 410 implants until AFTER sientra's FDA approval. So it IS confusing!  I think the term should be abandoned, since it is so confusing.All 3 breast implant companies in the USA make highly cohesive, high-strength cohesive, and cohesive silicone gel implants, each with a slightly different degree of cohesiveness, firmness (softness), rupture rate (fracture), and individual shapes (round and teardrop). None of these can "leak" so MRIs are a worthless test for this, IMHO.Thus, "gummy bear" = cohesive. NOT Sientra. But Sientra (and Mentor, and Allergan) make cohesive implants often called "gummy bear" implants by the lay public. Some lay persons, AND some plastic surgeons, use the term "gummy bear" only for the highy cohesive style 410 made by Allergan, and some use the term "gummy bear" only for the high-strength cohesive Sientra implants. Some use it for both of these two options, but not for the remainder of cohesive silicone gel (smooth round) implants. AAAARRRRGGGGHHHH!! Let's avoid this generic and confusing term and call implants what they really are. So much easier, and much more informative.For more information that may be of assistance to you in selecting type of implant, smooth or textured, shaped or round, saline or silicone (all are now cohesive), please click on the web reference link below. Whew! that was a lot, but I hope it helped. Best wishes! Dr. Tholen

The term “gummy bear” implant, which as far as I know was
initially coined by Dr. Grant Stevenson of Marina Del Rey, referred to the
Sientra textured round silicone implant. There is no true “gummy bear” implant
as this is just a nickname that was given because of the higher level of
cohesiveness of the gel. These days many surgeons refer to any type of silicone
implant as a “gummy bear” implant. With regards to cohesiveness and cross-linking, the silicone in 5th generation implants are either smooth round or
more form stable than Allergan and Mentor smooth round implants. All three
companies have significant form stability in their anatomical implants.

Thank you for the question. All currently FDA approved silicone gel breast implants are “cohesive”.  This “cohesiveness” makes it so that the silicone material is less likely to leak, if/when there is a failure of the surrounding shell.The “gummy bear” silicone material is a  more dense material chemically.  The term “gummy bear”  has been  used, almost as a slang term,  to encompass all silicone gel breast implants; thus the confusion. None  of the types of breast implants you mention are necessarily “better”; there are pros/cons associated with each type of implant. Every patient who presents for breast augmentation surgery has a different body type, different goals/concerns, and potentially a different “mindset” when it comes to the best breast implant for her. It is, therefore very important to individualize each patient's care.