Mechanical analysis of explanted silicone breast implants.

Smooth-walled silicone gel breast implants (n = 25) were removed from 15 women after implantation times that varied from 23 to 216 months (mean = 117 months; SEM = 12.9). Strips of implant shells were tested to failure by computer-controlled tensiometer. Regression analysis revealed significant negative correlation between age of implantation and shell strength (p < 0.05), shell toughness (p < 0.05), and shell elasticity (p < 0.05). These data suggest that exposure to the in vivo environment weakens silicone gel breast implant shells over time.