Dual surface modification of PDMS-based silicone implants to suppress capsular contracture

Publication date: Available online 14 June 2018
Source:Acta Biomaterialia
Author(s): Byoung Yong Yoo, Byung Hwi Kim, Jae Sang Lee, Byung Ho Shin, Heeyeon Kwon, Won-Gun Koh, Chan Yeong Heo
In this study, we report a new physicochemical surface on poly(dimethylsiloxane) (PDMS)-based silicone implants in an effort to minimize capsular contracture. Two different surface modification strategies, namely, microtexturing as a physical cue and multilayer coating as a chemical cue, were combined to achieve synergistic effects. The deposition of uniformly sized microparticles onto uncured PDMS surfaces and the subsequent removal after curing generated microtextured surfaces with concave hemisphere micropatterns. The size of the individual micropattern was controlled by the microparticle size. Micropatterns of three different sizes (37.16, 70.22, and 97.64 μm) smaller than 100 μm were produced for potential application to smooth and round-shaped breast implants. The PDMS surface was further chemically modified by layer-by-layer (LbL) deposition of poly-L-lysine and hyaluronic acid. Short-term in vitro experiments demonstrated that all the PDMS samples were cytocompatible. However, lower expression of TGF-β and α-SMA, the major profibrotic cytokine and myofibroblast marker, respectively, was observed in only multilayer-coated PDMS samples with larger size micropatterns (70.22 and 97.64 μm), thereby confirming the synergistic effects of physical and chemical cues. An in vivo study conducted for 8 weeks after implantation in rats also indicated that PDMS samples with larger size micropatterns and multilayer coating most effectively inhibited capsular contracture based on analyses of tissue inflammation, number of macrophage, fibroblast and myofibroblast, TGF-β expression, collagen density, and capsule thickness.Statement of SignificanceAlthough PDMS-based silicone implants have been widely used for various applications including breast implants, they usually cause typical side effect called as capsular contracture. Prior studies have shown that microtexturing and surface coating could reduce capsular contracture. However, previous methods are limited in application scope and difficult to obtain FDA approval because of large and non-uniform size of microtexture as well as the use of toxic chemical components. Here, those issues could be addressed by creating microtexture less than 100 μm with narrow size distribution and using layer-by-layer deposition of biocompatible polymer without using any toxic compounds. Furthermore, this is first attempt to combine microtexture with multilayer coating to obtain synergetic effects in minimizing the capsular contracture.

Graphical abstract

https://ift.tt/2HNaTiD