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A study of the aging of silicone breast implants using 29Si, 1H relaxation and DSC measurements

Paper ID Volume ID Publish Year Pages File Format Full-Text
12946 822 2004 9 PDF Available
Title
A study of the aging of silicone breast implants using 29Si, 1H relaxation and DSC measurements
Abstract

In this study 26 previously implanted silicone breast implants from the same manufacturer (Dow Corning) were investigated with two different analytical methods to characterize potential aging processes such as migration of monomer material from the gel and shell to local and distant sites, chemical alterations of the polymer, and infiltration of body compounds such as lipids. 1H and 29Si NMR relaxation measurements (spin–lattice, T1, and spin–spin, T2, relaxation times) were used to study the molecular dynamics of polysiloxane chains, both in gels and in shells. In addition, changes in physical properties were monitored by differential scanning calorimetry (DSC). The results of these measurements indicate that NMR relaxation times are influenced by implant generation, implantation time, shell texture and implant status. 1H T2 values of shells and gels show a tendency to increase with increasing implantation time, indicating higher mobility and possible disintegration of the polymer network of older implants. Furthermore, the data suggest that aging also involves the migration of low cyclic molecular weight (LMW) silicone and linear chain polymer material from the gels into the shells. The high “bleeding” rate of second-generation (G2) implants (implantation period around 1973–1985), exhibiting thin shells is reflected in reduced relaxation times of these devices, most likely due to a loss of low molecular weight fractions from the gels. Moreover, “gel bleeding” also influences the melting behavior observed in DSC studies. Increased shell rigidity (high Tm and Tg) tends to be correlated with longer 29Si relaxation times of the corresponding gels, suggesting a reduced transfer of LMW silicones and linear chain polymer from the gel to the shell and to the outside. Remarkably, textured implants seem to be less susceptible to degradation processes than implants with thin shells.

Keywords
NMR relaxation time; Silicone implants; DSC; Aging
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A study of the aging of silicone breast implants using 29Si, 1H relaxation and DSC measurements
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Publisher
Database: Elsevier - ScienceDirect
Journal: Biomaterials - Volume 25, Issue 18, August 2004, Pages 4405–4413
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us