Breast augmentation remains as one of the most popular and successful of all cosmetic plastic surgery procedures. The biggest decision any woman makes (beyond deciding to undergo the operation) in considering breast augmentation is the choice between saline and silicone breast implants. One consideration in making this choice is to consider the risk of device (breast implant) failure over their lifetime.
All breast implants may eventually develop a hole or tear in the ‘bag’, known as fatigue failure of the containment shell. This is a risk for every patient and eventually most breast augmentation patients will experience this risk. It is a natural phenomenon that develops over time through the motion of the implant’s wall as it is displaced by external pressures on the breast. Even though the containment sac or shell that contains either silicone or saline is soft and flexible, at the microscopic level it is a more rigid plastic. Eventually a crack (fatigue failure) will develop in it and this crack will propagate and become a more visible hole or tear. Once this becomes a full-thickness failure, the material inside has an opportunity to escape outward.

Silicone breast implant failure is different because the silicone gel inside the bag does not act like water. Rather it is a thick viscous gel that behaves more like jello. It is sticky or cohesive and does not flow due to bonding of the silicone molecules to each other. The gel material is somewhere between a liquid and a solid. Because it does not flow, it can not come out of the hole or tear unless it is quite large. Even then it will only bulge out when the implant is squeezed but will go back in as soon as the pressure is off of the implant. This failure process, rather than be called deflation, is known as silent rupture because it is not possible to tell on the outside that the implant has failed. The only way to know for sure is to get a mammogram as this test squeezes the breast implant and can make the bulge evident. Even an MRI may not be able to detect a silicone gel implant rupture as this test does not put any pressure on the implant.
Based on the different ways that saline and silicone breast implants fail, it is fair to say that the need to replace saline breast implants over a patient’s lifetime is higher than silicone. Simply because all saline implant failures can be seen and cause an immediate adverse change in the breast. Most silicone breast implant failures will not be seen and cause no external change in the appearance of the breast.
Dr. Barry Eppley
Indianapolis, Indiana
