The FDA approved silicone implants for use in cosmetic augmentation in 2006.  This has added a great option for many patients but also added some confusion as to which type of implant is best for a particular patient.  The most important difference between silicone gel and saline filled implants is the issue of rupture.  All breast implants, being artificial devices, have to behave in a friendly biological fashion to integrate appropriately in living tissue.  They also must have properties that make them desirable for their intended use.  Softness, pliability, and shape are important properties but these characteristics play a role in the longevity of the device.  Currently, the major manufacturers of breast implants in this country (Mentor and Allergan) list an anticipated longevity of ten years for their implants.  However, there is no guarantee that any implant will last for any specified period of time.  Although we discuss the rupture rate in terms of a percent each year, it stands to reason that the rupture rate for a breast implant is 100% – eventually.  Rupture is really where the 2 types of implants part ways in a practical sense.  The saline implant, filled with salt water, will simply deflate over a period of days following rupture.  The loss of volume is immediate and usually quite noticeable to the patient.  No special test is necessary to confirm what is obvious. The filler, salt water in this case, is simply absorbed by the body and excreted by the kidneys in the usual fashion.

Silicone gel filled implant rupture is another matter.  The filler in this case, a cohesive silicone gel, is not absorbed by the body.  Therefore, the volume of the breast changes little following rupture.  Although there is a chance of a slight change in the shape and/or feel of the implant following rupture, it is well known that this change is subtle, and will likely be missed by both the patient and her surgeon.  The FDA required labeling consistent with this problem, recommending MRI screening for silicone breast implants beginning at three years post implantation followed by every other year thereafter.  Unfortunately, the MRI is not without its own problems.  There is a significant false positive rate on screening (it sees a rupture when there isn’t).  It is also expensive, not being covered by health insurance when the implants were placed for cosmetic purposes.  I encourage all of my patients with silicone-gel filled implants to carefully consider the FDA recommendations for MRI screening.  As more information becomes available for these devices, modification of the current recommendation should follow.

So, why would a woman choose one implant over another?

While it is true that both saline filled and silicone-gel filled breast implants are effective in providing larger, more shapely breasts, some women benefit from the better texture and more natural feel of the silicone-gel filled breast implant. For example, smaller breasted women typically benefit most from the silicone-gel filled implant as the presence of any implant is more difficult to conceal. There is less fat and breast tissue to cover the implant, and so problems such as wrinkling can be more severe. In addition, women who have had children can experience involution of the breast gland, leaving a softer, thinner breast which may feel strange over a the typically firmer saline implant.

So how does a patient choose?

Except in the specific circumstances noted above, it is very hard to tell the difference simply by looking.  They are both good at making breasts round and full.  Most of the improvement in result is largely due to texture and feel.  This makes it a personal choice by the patient based on her own goals.  As proof to myself, I have been present at international meetings of plastic surgeons where photographs of patients with breast implants are shown on the screen.  The surgeon audience members are then asked to vote, “Saline or Silicone?”  We plastic surgeons cannot guess any better than chance!  Of course photographs are not the same as the real thing, but it certainly makes a point.  The bottom line is that the decision rests with the patient.  My job is to relate the facts and make recommendations based on sound surgical practice