Editing Breast augmentation (section)

==Surgical breast augmentation==
===Breast implants===
There are four types of implants:

# Saline implants filled with sterile [[saline (medicine)|saline solution]].
# Silicone implants filled with viscous [[silicone|silicone gel]].
# Alternative-composition implants (no longer manufactured), filled with various fillers such as [[soy|soy oil]] or [[String breast implant|polypropylene string]].
# "Structured" implants using nested elastomer silicone shells with saline between the shells.<ref name="PRSINichter"/>

====Saline breast implant====
The saline breast implant, filled with [[Saline (medicine)|saline solution]], was first manufactured by the Laboratoires Arion company, in France, and introduced for use as a prosthetic [[medical device]] in 1964. Modern-day versions of saline breast implants are manufactured with thicker, room-temperature [[Vulcanization|vulcanized]] (RTV) shells made of a [[silicone]] [[elastomer]]. The study ''In vitro Deflation of Pre-filled Saline Breast Implants'' (2006) reported that the rates of deflation (filler leakage) of the pre-filled saline breast implant made it a second-choice prosthesis for "corrective breast surgery".{{clarify|date=February 2020}}<ref name="Stevens">{{cite journal|vauthors=Stevens WG, Hirsch EM, Stoker DA, Cohen R |s2cid=41156555 |title=In vitro Deflation of Pre-filled Saline Breast Implants | journal=Plastic and Reconstructive Surgery | year=2006|pages=347–349| volume=118|issue=2|pmid=16874200|doi=10.1097/01.prs.0000227674.65284.80}}</ref> Nonetheless, in the 1990s, the saline breast implant was mandated to be the prosthesis usual for breast augmentation surgery, the result of the U.S.  [[Food and Drug Administration]]'s (FDA) temporary restriction against the importation of silicone-filled breast implants.{{citation needed|date=February 2020}}

The technical goal of the saline-implant technique was a less-invasive surgical technique, by inserting an empty, rolled-up breast implant through a smaller surgical incision.<ref name="Arion1965">{{cite journal|author=Arion HG|title=Retromammary Prosthesis |journal=Comptes Rendus de la Société Française de Gynécologie | year=1965|volume=5}}</ref> In surgical practice, after having installed the empty breast implants in the implant pockets, the plastic surgeon would then fill each device with saline solution through a [[one-way valve]] and, because the required insertion incisions were short and small, the resultant incision scars would be smaller and shorter than the surgical scars typical of the pre-filled, silicone-gel implant surgical technique.<ref>{{Cite journal |date=January 2004 |title=Saline-Filled Breast Implant Surgery: Making an Informed Decision |url=https://www.hopkinsmedicine.org/plastic_reconstructive_surgery/_downloads/saline_filled_breast_implant_surgery_brochure.pdf |website=hopkinsmedicine.org}}</ref>

When compared with the results achieved with a silicone-gel breast implant, the saline implant can yield "good-to-excellent" results of increased breast size, a smoother hemisphere contour, and realistic consistency; yet it is likelier to cause cosmetic problems, such as the rippling and the wrinkling of the breast-envelope skin, and technical problems, such as the implant's presence being noticeable to the eye and to the touch. The occurrence of such cosmetic problems is likelier in the case of a person with very little breast tissue; in the case of a person who requires [[Mastectomy|post-mastectomy]] breast reconstruction, the silicone-gel implant is the technically superior [[Prosthesis|prosthetic]] device for [[breast reconstruction]]. In the case of a person with much breast tissue, for whom sub-muscular placement is the recommended surgical approach, saline breast implants can give an aesthetic result much like that produced by silicone breast implants: an appearance of proportionate breast size, smooth contour, and realistic consistency.<ref>{{cite journal | author = Eisenberg, TS | title = Silicone Gel Implants Are Back—So What? | journal = American Journal of Cosmetic Surgery | year = 2009 | volume = 26 | pages = 5–7 | doi=10.1177/074880680902600103| s2cid = 136191732 }}</ref>

====Silicone-gel breast implant====
The modern [[breast implant|prosthetic breast]] was invented in 1961, by the American [[Plastic surgery|plastic surgeons]] Thomas Cronin and Frank Gerow, and manufactured by the [[Dow Corning Corporation]]; in due course, the first augmentation mammoplasty was performed in 1962.<ref>{{Cite web |title=The History of Breast Aesthetics |url=https://polytech-health-aesthetics.com/en/blog/article/history-breast-aesthetics/ |access-date=2023-03-02 |website=polytech-health-aesthetics.com |date=19 January 2021 |language=en}}</ref> There are five generations of [[medical device]] [[technology]] for the breast-implant models filled with silicone gel; each generation of breast prosthesis is defined by common model-manufacturing techniques.

====First generation====
The Cronin–Gerow implant, prosthesis model 1963, was a silicone rubber envelope-sack, shaped like a teardrop, which was filled with viscous silicone-gel.<ref>{{Cite web |title=The Development of Silicone Breast Implants for Use in Breast Augmentation Surgeries in the United States {{!}} The Embryo Project Encyclopedia |url=https://embryo.asu.edu/pages/development-silicone-breast-implants-use-breast-augmentation-surgeries-united-states |access-date=2023-03-02 |website=embryo.asu.edu}}</ref> To reduce the rotation of the emplaced breast-implant upon the chest wall, the model 1963 prosthesis was affixed to the implant pocket with a fastener-patch, made of Dacron material ([[polyethylene terephthalate]]), which was attached to the rear of the breast implant shell.<ref name=Cronin_1963>{{cite journal |vauthors=Cronin TD, Gerow FJ | title = Augmentation Mammaplasty: A New "natural feel" Prosthesis | journal = Excerpta Medica International Congress Series | year = 1963 | volume = 66 | page = 41}}</ref>

====Second generation====
In the 1970s, manufacturers offered the second generation of breast implant prostheses
* The first developments were a thinner-gauge implant shell, and a filler gel of low-cohesion silicone, which made the devices more functional and realistic (size, appearance, and [[consistency]]). Yet, in clinical practice, second-generation breast implants proved fragile, with greater rates of shell rupture and filler leakage ("silicone-gel bleed") through the "intact device's shell. The consequences, plus increased rates of [[capsular contracture]], precipitated faulty product [[Class action|class action-lawsuits]] by the U.S. government against the Dow Corning Corporation and other manufacturers of breast prostheses.
* The second technological development was a [[polyurethane|polyurethane foam coating]] for the shell of the implant; the coating reduced the degree of capsular contracture by causing an [[Inflammation|inflammatory reaction]] that impeded the formation of a capsule of fibrous [[collagen]] tissue around the coated device. Nevertheless, despite the intentions behind the polyurethane foam coating, the medical use of polyurethane-coated breast implants was briefly discontinued due to the potential health risk posed by 2,4-toluene diamine (TDA), a [[carcinogen]]ic by-product of the chemical breakdown of the polyurethane foam coating of the breast implant.<ref name="Luu11998">{{cite journal |vauthors=Luu HM, Hutter JC, Bushar HF | title=A Physiologically Based Pharmacokinetic Model for 2,4-toluenediamine Leached from Polyurethane foam-covered Breast Implants | journal=Environ Health Perspect | year=1998 | pages=393–400 | volume=106 | issue=7 | pmid=9637796 | doi=10.2307/3434066 | pmc=1533137 | jstor=3434066}}</ref>{{pb}} After reviewing the medical data, the FDA concluded that TDA-induced [[breast cancer]] was an infinitesimal health risk to anyone with breast implants, and did not justify legally requiring physicians to explain the matter to their patients. Ultimately, polyurethane-coated breast implants remain in plastic surgery practice in Europe and in South America; no manufacturer has sought FDA approval for medical sales of such breast implants in the U.S.<ref>{{cite journal |author1=Hester TR Jr |author2=Tebbetts JB |author3=Maxwell GP | title=The Polyurethane-covered Mammary Prosthesis: Facts and Fiction (II): A Look Back and a "peek" Ahead | journal=Clinical Plastic Surgery | year=2001 | pages=579–86 | volume=28 | issue=3 |doi=10.1016/S0094-1298(20)32397-X | pmid=11471963}}</ref>
* The third technological development was the double-lumen breast implant, a double-cavity prosthesis composed of a silicone breast implant contained within a saline breast implant. The two-fold, technical goal was: (i) the cosmetic benefits of silicone gel (the inner lumen) enclosed in saline solution (the outer lumen); and (ii) a breast implant whose volume is post-operatively adjustable. Unfortunately, the more complex design of the double-lumen breast implant had a device-failure rate greater than that of single-lumen breast implants. This style of implant, in modern times, is primarily used for [[Reconstructive surgery|breast reconstruction]].<ref>{{Cite journal |date=March 2022 |title=History of breast implants: Back to the future |journal=JPRAS Open |pmid=35434240 |pmc=9006741 |last1=Di Pompeo |first1=F. S. |last2=Paolini |first2=G. |last3=Firmani |first3=G. |last4=Sorotos |first4=M. |volume=32 |pages=166–177 |doi=10.1016/j.jpra.2022.02.004 }}</ref>

====Third and fourth generations====
In the 1980s, the third- and fourth-generation implants were stepwise advances in manufacturing technology, such as [[elastomer]]-coated shells that decreased gel bleed (filler leakage), and a thicker, increased-cohesion filler gel. The manufacturers of implantable breast prostheses then designed and made anatomic models (like the natural breast) and "shaped" models, which realistically corresponded with the breast and body types of actual women. The tapered models of breast implants have a uniformly textured surface, to reduce rotation of the prosthesis within the implant pocket; round models of breast implants are available in both smooth-surface and textured-surface models, as rotation is not an issue.

====Fifth generation====
Since the mid-1990s, the fifth generation of silicone gel breast implants is made of a semi-solid gel, which mostly eliminates the occurrences of filler leakage ("silicone-gel bleed") and of the migration of the silicone filler from the implant-pocket to other areas of the person's body. The studies ''Experience with Anatomical Soft Cohesive Silicone gel Prosthesis in Cosmetic and Reconstructive Breast Implant Surgery'' (2004) and ''Cohesive Silicone gel Breast Implants in Aesthetic and Reconstructive Breast Surgery'' (2005) reported relatively lower rates of [[capsular contracture]] and of device-shell rupture, and relatively  greater rates of "medical safety" and "technical efficacy" than those of early-generation breast implants.<ref>{{Cite journal | doi = 10.1097/01.prs.0000176259.66948.e7 | last1 = Brown | first1 = M. H. | last2 = Shenker | first2 = R. | last3 = Silver | first3 = S. A. | title = Cohesive silicone gel breast implants in aesthetic and reconstructive breast surgery | journal = Plastic and Reconstructive Surgery | volume = 116 | issue = 3 | pages = 768–779; discussion 779–1 | year = 2005 | pmid = 16141814| s2cid = 35392851 }}</ref><ref>{{Cite journal | last1 = Fruhstorfer | first1 = B. H. | last2 = Hodgson | first2 = E. L. | last3 = Malata | first3 = C. M. | s2cid = 24661896 | title = Early experience with an anatomical soft cohesive silicone gel prosthesis in cosmetic and reconstructive breast implant surgery | journal = Annals of Plastic Surgery | volume = 53 | issue = 6 | pages = 536–542 | year = 2004 | pmid = 15602249 | doi=10.1097/01.sap.0000134508.43550.6f}}</ref><ref>{{Cite journal | last1 = Hedén | first1 = P. | last2 = Jernbeck | first2 = J. | last3 = Hober | first3 = M. | title = Breast augmentation with anatomical cohesive gel implants: The world's largest current experience | journal = Clinics in Plastic Surgery | volume = 28 | issue = 3 | pages = 531–552 | year = 2001 | doi = 10.1016/S0094-1298(20)32393-2 | pmid = 11471959}}</ref>

====Alternative-composition implants====
Saline and silicone gel are the most common types of breast implant used in the world today.<ref name="TalesForTaglicozzi">{{cite book |last1=Zannis |first1=John |title=Tales for Tagliacozzi: An Inside Look at Modern-Day Plastic Surgery |date=2017 |publisher=AuthorHouse |isbn=9781524659073 |url=https://books.google.com/books?id=z9YADgAAQBAJ&q=Alternative-composition+implants+soy&pg=PT19 |access-date=2 December 2017}}</ref> Alternative-composition implants have largely been discontinued. These implants featured fillers such as soy oil and polypropylene string. Other discontinued materials include ox [[cartilage]], [[Terylene]] "wool", ground [[rubber]], [[silastic]] rubber, and [[Teflon]]-silicone prostheses.<ref name="TalesForTaglicozzi"/>

===="Structured" implants====
Structured implants were approved by the FDA and Health Canada in 2014 as a fourth category of breast implant.<ref name="PRSINichter">{{cite journal |last1=Nichter |first1=Larry S. |last2=Hardesty |first2=Robert A. |last3=Anigian |first3=Gregg M. |title=IDEAL IMPLANT Structured Breast Implants: Core Study Results at 6 Years |journal= Plastic and Reconstructive Surgery|volume=142 |issue=1 |pages=66–75 |date=July 2018 |doi=10.1097/PRS.0000000000004460 |pmid=29489559 |pmc=6045953 }}</ref> These implants incorporate both saline and silicone gel implant technology. The filler is saline solution, in case of rupture, and has a natural feel, like silicone gel implants.<ref>{{cite news |title=What types of breast implants are available? |url=https://www.plasticsurgery.org/cosmetic-procedures/breast-augmentation/implants |publisher=American Society of Plastic Surgeons}}</ref> This implant type uses an internal structure consisting of three nested silicone rubber "shells" that support the upper half of the breast, with the two spaces between the three shells filled with saline. The implant is inserted, empty, then filled once in place, which requires a smaller incision than a pre-filled implant.<ref name="PRSINichter"/>

===Implants and breastfeeding===
The breasts are [[Apocrine|apocrine glands]] which produce [[milk]] for the feeding of infant children,<ref name="Tortora, Gerard J.">Tortora, Gerard J. ''Introduction to the Human Body'', Fifth Edition. John Wiley & Sons, Inc.: New York, 2001. p. 560.</ref>

[[File:Breast anatomy normal scheme.png|thumb|right|upright=0.9|Breast augmentation: cross-section scheme of the [[mammary gland]]. {{ordered list |[[Chest wall]] |[[Pectoralis muscle]]s |[[Lobules]] |[[Nipple]] |[[Areola]] |[[Lactiferous duct|Milk duct]] |[[Adipose tissue|Fatty tissue]] |[[Human skin|Skin envelope]]}}]]

[[File:Asymmetric breastfeeding latch.jpg|thumb|right|upright=0.9|A functional breast: a mammary gland feeding an infant child.]]

====Breast implant toxicity====
Digestive tract contamination and systemic toxicity due to the leakage of breast implant filler to the breast milk are the principal infant health concerns with breast implants. Breast implant fillers are biologically inert: [[silicone]] filler is [[Digestion|indigestible]] and saline filler is mostly salt and water. Each of these substances should be chemically inert and present in the environment.{{citation needed|date=February 2020}}<!--sources must somehow make the doubtful case that silicones are ubiquitous in modern life--> Moreover, "proponent" physicians have stated that there "should be no absolute contraindication to breast-feeding by women with silicone breast implants."<ref>{{cite journal|author=Berlin, C. M. |title=Silicone Breast Implants and Breast-feeding|journal= Pediatrics |year=1994|volume= 94|pages=546–549|pmid=7936870|issue=4 Pt 1|doi=10.1542/peds.94.4.547|s2cid=245120428}}</ref> In the early 1990s, at the beginning of the silicone gel breast implant illness panic, small-scale, non-randomized studies indicated possible breast-feeding complications from silicone implants; no one study was able to demonstrate disease causality due to implants.<ref name="berlin1996">Berlin, Cheston M. Jr. [http://www.llli.org/ba/Feb96.html Silicone Breast Implants and Breastfeeding] {{Webarchive|url=https://web.archive.org/web/20101231065024/http://www.llli.org/ba/Feb96.html |date=2010-12-31 }}, Hershey Medical Center, Hershey, Pennsylvania; from Breastfeeding Abstracts. February 1996, Volume 15, Number 3, pp. 17–18.</ref>

====Impediments to breastfeeding====
A person with breast implants is usually able to [[Breastfeeding|breastfeed]] an infant; yet implants can cause functional breastfeeding difficulties, especially with [[mammoplasty]] procedures that involve cutting around the areola, and implant placement directly beneath the breast, which tend to cause greater breast-feeding difficulties. Patients are advised to select a procedure that causes the least damage to the [[lactiferous duct]]s and the nerves of the nipple-areola complex (NAC).<ref>[http://www.llli.org/NB/NBsurgery.html Breastfeeding after Breast Surgery] {{Webarchive|url=https://web.archive.org/web/20101230173437/http://www.llli.org/NB/NBsurgery.html |date=2010-12-30 }}, La Leche League (2009-09-05).</ref><ref>[http://www.llli.org/cbi/bibimplant.html Breastfeeding and Breast Implants] {{Webarchive|url=https://web.archive.org/web/20101231121338/http://www.llli.org/cbi/bibimplant.html |date=2010-12-31 }}, Selected Bibliography April 2003, LLLI Center for Breastfeeding Information.</ref><ref name="slate">Beam, Christopher (2009-12-11). [http://slate.com-Il.info/articles/news_and_politics/explainer/2009/12/inorganic_milk.html Inorganic Milk: Can Kendra Wilkinson breast-feed her baby even though she has implants?] {{Webarchive|url=https://web.archive.org/web/20160507045146/http://slate.com-il.info/articles/news_and_politics/explainer/2009/12/inorganic_milk.html |date=2016-05-07 }}, [[Slate.com]].</ref>

Functional breastfeeding difficulties arise if the surgeon cuts the milk ducts, the major nerves innervating the breast, or if the milk glands are otherwise damaged. Some surgical approaches, including IMF (inframammary fold), TABA (trans-axillary breast augmentation), and TUBA ([[trans-umbilical breast augmentation]]), avoid the tissue of the nipple-areola complex; if the person is concerned about possible breast-feeding difficulties, the periareolar incisions can sometimes be made so as to reduce damage to the milk ducts and to the nerves of the NAC. The milk glands are affected most by subglandular implants (under the gland) and large-sized breast implants, which pinch the lactiferous ducts and impede milk flow. Small-sized breast implants, and submuscular implantation, cause fewer breast function problems; however, some women have managed to successfully breastfeed after undergoing periareolar incisions and subglandular emplacement.<ref name="slate"/>