Breast Implants

The female breast is regarded as a symbol of femininity. Deviations from the normal size, shape and symmetry are interpreted as unattractive. Attractive breast augmentation can give such a positive sense of self-esteem, self-confidence, a sense of well-being and happiness. This in turn positively affects family relationships, friendships and work relationships. Augmentation can therefore, manage both physical and emotional disorders. Breast implants are continually heightening in popularity.

When considering breast implant surgery, there are several elements to be considered. The following links provide important information on breast implants;

• Brazilian Implants
• What is Silicone?
• History of Breast Implants
• Indications for Augmentation

Further Reading:

• Basic Considerations
• Breast Implant Design
• Breast Implant Surgery
• Breast Implant Complications

Brazilian Implants

They were introduced in the 1970’s.

They are covered with polyurethane foam.

The incidence of capsular contraction is dramatically lower compared to either smooth or textured implants. The literature quotes just 1-2% with a 15 year follow up, down from 8-9% with other types of implants.

Non polyurethane implants elicit a relatively short-lived, avascular and acellular inflammatory response. Collagen fibres are deposited in a parallel, linear array. As contraction occurs, the parallel orientation predisposes to linear contracture, resulting in spherical deformity and firmness of the implant.

When polyurethane is implanted it causes an intense foreign body reaction with neo-vascularisation and infiltration of large numbers of histiocytes and foreign body giant cells. Collagen fibres are deposited in a configuration that mirrors the open cell architecture of the foam. This results in a unique sponge like scar tissue capsule.

“This discovery perhaps explains the absence of capsular contraction amongst most polyurethane covered mammary implants”. (Brand. K. Gerard. Plastic Reconstr. Surg. 1984).

This does occasionally cause an allergic skin rash (1-2%). It generally begins within 2 weeks of surgery and is characterised by diffuse erythematous (redness) rash and pruritis (itching) and subsides spontaneously within 2 – 4 weeks. It can be treated with anti-histamines.

Rippling occurs mostly in the superior pole of the breasts and along the inferior edge. This has the same incidence in all implants. Ripples are the result of the combination of tight pouches with insufficient tissue cover. A sub-muscular plane may help prevent this phenomenon. The sub muscular plane is also used as it is thought to decrease the incidence of capsular contraction. A major benefit of polyurethane implants is being able to use the natural result of the sub glandular plane without the fear of increasing the rate of capsular contracture. This does therefore lead to a greater flexibility in the choices that can be made pre-operatively.

All the other local complications are the same as smooth or textured implants 
i.e.

• infection (less than 1%)
• haematomas (0.9 – 2.3 %)
• implant rupture (0.3 – 1.4%)

There is less rotation as the porous implant surface sticks to the fibrotic capsule like Velcro. Polyurethane foam used as a coating undergoes gradual chemical degradation. Chemical analysis using gas chromatography has confirmed the presence of small amounts of 2, 4 – toluenediamine in the urine but it has not been detected in serum (blood). It is thought that the quantity released is not carcinogenic in humans (2,4-TDA is a known rodent carcinogen).

The FDA, the North American Food and Drug Administration Agency, said “based on the very small quantities of TDA found in urine, the potential risk of cancer, if any, is probably negligible”. The FDA estimates that the excessive risk of cancer as a result of exposure to TDA is around one in a million in a woman’s lifetime.

There is historical evidence to support the safety of polyurethane foam in medical devices. Polyurethanes have been implanted for decades in pacemaker connectors, haemodialysis tubing, percutaneous shunts, vascular patches and grafts.

In conclusion, the capsular contraction rate after all types of breast surgery is lower with polyurethane foam covered implants. This benefit persists long term, at least ten years after implantation.

“One particular feature is that the implant remains behind the breast and follows it in all its natural movements instead of displacing itself freely throughout the capsular space”. (Vasquez M.D. Pg 334)

“There is nothing in the experimental literature to suggest that polyurethane foam, or its in vivo breakdown products, pose a threat to the health or safety of patients”. (Handel, N M.D. Pg 272)

Sources

1. Brand, K.G. Polyurethane coated silicon implants and questions on capsular contraction. Plast. Reconstr. Surg. 1984.)
2. Handel, N, M.D. Long term safety and efficiency of polyurethane foam covered breast implants. Aesth. Surg. 2006. 265 – 274)
3. Vàsquez, G, M.D. and Pellòn, A, M.D. Polyurethane Coated Silicon Gel Breast Implants used for 18 years. Aesth. Plast. Surg. 31: 330-336, 2007.
4. Forum on polyurethane mammary implants. Brazilian Plastic Surgery Society. July 30th & 31st,2007.

What is Silicone?

Silicones are a family of chemical compounds. They are made from silicon, a naturally occurring element found in sand, quartz and rock. After oxygen, silicon is the most common element in the earths crust, and becomes silicone when it is combined with oxygen, carbon and hydrogen. Short chains are liquid, progressing to gel, foam and finally a hard resin or rubbery material, called elastomers. A silicone implant has an elastomer outer layer which can be smooth or rough (textured) and an inner gel with different consistencies. Some implants also have a protective barrier between two elastomer layers to reduce any possible gel diffusion.

Another form of silicone is dimethicone. This is found in hairsprays, suntan lotions and moisturising creams. The liquid form is for coating surgical needles and suture thread and in the interior surfaces of syringes and bottles used for storage of blood. Protective silicone coatings are used in pacemakers and heart valves. Silicones are also used in artificial joints, catheters, drainagesystems, facial implants and tissue expanders.

Silicone products have been found to be biocompatible (accepted by the human body without adverse reaction), reliable, flexible and easy to sterilize. This makes them ideal for use as implants.

History of Breast Implants

In the early 1960′s the silicone gel-filled implants were developed to improve options for women who needed mastectomies to treat breast cancer. These implants were very different to the ones made today. They had a smooth envelope which was not as strong as the outer covering today and were prone to rupture. Also through this one layer there was diffusion of silicone gel. This silicone was also liquid and could infiltrate into the surrounding tissues. Today it is a viscous gel, much like toothpaste. This is quite sticky and can possibly cause a local inflammatory reaction but will not spread everywhere.

In the early 1990′s the capsules were made thinner in France and America to improve the texture and more closely mimic natural full breasts. More ruptured and claims were made that this caused connective tissue diseases eg scleroderma, rheumatoid arthritis or systemic lupus erythematosus. In America some regulatory authorities imposed restrictions on the use of silicone implants. Many surgeons starting using saline filled implants but these still have a silicone elastomere covering.

Since then silicone has been extensively tested in laboratory studies as well as clinical studies. In 1986 the University of Southern California studied 3000 women in Los Angeles who had implants between 1959 and 1980. In 1992 a Georgia, New Jersey, and Washington study investigated over 2000 women. All these studies found no increased risk of breast cancer following breast implant surgery.

In 1994 the Mayo Clinic compared 749 women who had breast mplant surgery with 1498 women who did not have implants. This study found no association between breast implants and connective tissue diseases.

Connective tissue disorders occur independently in the general population. Statistically,women have a higher incidence of auto-immune disease than men. These types of diseases may occur coincidentally along with implants. This does not mean the implants caused the disorders. The cause and effect relationship between breast implants and these diseases has never been proven.

Indications for Augmentation, include;

• Aplasia
• Hypoplasia (i.e. small breasts)
• Asymmetry
• Tuberous breast shape
• Idiopathic involution ((Where a once normal-sized breast shrinks following pregnancy or weight loss) )
• Reconstruction following mastectomy
• It is not indicated when a troubled relationship needs mending, when there is major depression or a psychiatric illness or when general health is poor
• To improve self-image and to look better in and out of clothing
• To obtain fuller breasts and a more feminine and proportional figure.