The Core of the Implant: Understanding Medical-Grade Silicone
At the heart of many modern implants, including breast implants, is silicone. This synthetic polymer is derived from silicon, a natural element found in quartz and sand. Through extensive chemical processing, silicon is converted into silicone, which can take various forms—from a liquid to a rubbery solid. For medical use, it is purified and formulated to be highly inert and compatible with human tissue, a property known as biocompatibility.
The Anatomy of an Implant
To understand the rubbery substance in implants, it's crucial to distinguish between the two main components that contain silicone:
- The Outer Shell (Elastomer): Every silicone and saline implant features a solid, rubbery, silicone elastomer outer shell. This shell provides the structure and durability of the implant. Its surface can be either smooth or textured, with the latter designed to encourage surrounding tissue to grow into it, potentially reducing the risk of capsular contracture. These shells are built in layers, with inner barrier layers added in newer models to minimize gel “bleed,” or the seepage of silicone molecules through the shell.
- The Filler: The substance inside the shell determines the type of implant. While saline implants are filled with a sterile salt-water solution, silicone gel implants contain a cohesive silicone gel. It is this filler that many people think of as the primary rubbery substance.
The Evolution of the Silicone Gel
Early silicone implants used a more fluid-like gel. However, modern silicone gel has evolved significantly, leading to the development of highly cohesive gels often dubbed “gummy bear” implants. This nickname comes from their resemblance to the candy, as the gel is thick enough to hold its form even if the implant shell is torn. This innovation was a major step forward in implant safety and patient peace of mind, as it prevents the filler from leaking into surrounding tissue in case of a rupture.
A Comparison of Implant Types
Choosing an implant requires understanding the differences between the main types. While both use a silicone shell, their internal composition provides distinct characteristics.
| Feature | Saline Implants | Silicone Gel Implants |
|---|---|---|
| Fill Material | Sterile saltwater solution | Cohesive silicone gel |
| Feel | Can feel firmer, sometimes with a noticeable “sloshing” effect in older models. Newer models have improved feel. | Often described as more natural and softer, closely mimicking the feel of breast tissue. |
| Rupture Detection | Immediately noticeable due to deflation of the implant as the saline is absorbed harmlessly by the body. | Requires imaging, typically an MRI, to detect rupture as the cohesive gel remains contained and the implant maintains its shape. |
| Surgical Incision | Smaller incision, as the shell is inserted and then filled in place. | Larger incision, as the implant is inserted pre-filled. |
| FDA Approval Age | 18+ for augmentation | 22+ for augmentation |
Advancements in Implant Safety and Longevity
Thanks to continuous research and development, implant technology has made considerable progress. Today's silicone implants are significantly more advanced than their predecessors. The multi-layered shells are stronger, and the cohesive gel is a major safety feature. The use of textured surfaces, though now used with greater caution and less frequently due to links with specific rare complications, has also played a role in minimizing capsular contracture.
However, it is crucial to remember that implants are not lifetime devices. All implants carry a risk of complications and will likely require replacement at some point. Regular follow-up appointments with a surgeon and appropriate imaging, such as an MRI for silicone implants, are essential for long-term health and monitoring.
For more detailed information on safety, refer to the National Academies Press report on silicone breast implants.
Long-Term Monitoring and Potential Complications
Despite improvements, it's important to be aware of the potential issues associated with implants. A common complication for both saline and silicone implants is capsular contracture, which occurs when scar tissue around the implant hardens and tightens, leading to pain and breast distortion. In the event of an implant rupture, the outcomes differ:
- Saline rupture: The implant deflates, and the body harmlessly absorbs the saline. A visible cosmetic change immediately signals the need for replacement.
- Silicone rupture: Because of the cohesive gel, a rupture may go unnoticed initially. This is known as a "silent rupture." The gel typically stays contained within the scar capsule. Monitoring with an MRI is recommended to detect such issues.
Over the years, there were widespread fears linking silicone implants to systemic diseases like lupus and rheumatoid arthritis. Extensive studies, however, have not found a definitive link between silicone breast implants and major systemic diseases. While some women do experience health issues, the evidence suggests these are no more common in those with implants than in the general population. This scientific consensus helps reassure individuals considering implants about their safety profile regarding major illnesses, though local complications and the non-lifetime nature of the devices remain important considerations.
Conclusion
In summary, the rubbery substance in implants is a carefully crafted, medical-grade silicone. This material is used to create the durable outer shell of all modern implants and, in the case of silicone implants, a highly cohesive gel filler. Significant advances, such as the "gummy bear" gel and stronger shells, have enhanced the safety and performance of implants over time. While not a permanent solution, continuous monitoring and regular check-ups with a medical professional allow individuals with implants to manage their long-term health effectively.
