Incorporation of metallic nanoparticles in silicone breast implants for reduction of capsular contracture

Capsular contracture (CC) is one of the most common clinical complications following breast augmentation or reconstruction surgery using implants. The bacterial infections that arise following surgical procedures and the foreign body reactions due to the hydrophobicity of the silicone elastomer implants are problematic and are believed to be important in the development of CC. One of the most common strategies implemented to reduce foreign body reactions has been use of breast implants (BIs) with textured surfaces. While this approach has led to reduced incidence of fibrous capsule formation around implants, it has also led to an association with anaplastic large cell lymphomas (BIA-ALCL) which has led to the withdrawal of certain textured surfaces from many countries by health authorities. With the withdrawal of macrotextured implants from the market, new strategies are needed to reduce rates of CC. Metallic ions and nanoparticles (NPs) - such as copper (Cu) and zinc (Zn) - have been reported effective anti-bacterial agents against Staphylococcus epidermidis (S. epidermidis), Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), each suspected to provoke strong CC reactions. Therefore, incorporation of anti-bacterial metal NPs into either the silicone shell or gel components of BIs offers an alternative pharmacological strategy to reduce the risks of CC and implant associated infection. Here we studied the incorporation of the NPs into a silicone dispersion commonly used to manufacture the shell of BIs.