Answer:
Texturing the implant apparently modifies the response of surrounding soft tissue to the implant and can retard the development of an organized tight collagen capsule. In rat models, textured implants were found to alter the linear arrangement of the fibroblasts and myofibroblasts along the shell surface and deform the laminar collagen pattern into an irregular waveform pattern. Pollack (PRS 1993; 91:404) retrospectively compared 98 consecutive patients with smooth Mentor implants with 99 who had Siltex textured-surface implants. After a mean follow-up of 18 months, Baker III or IV contractures developed in 21% of those with smooth implants compared to 4% in those with textured implants. In contrast, Handel (PRS 1995; 96:1521) retrospectively studied implants including textured, smooth, silicone, saline, and polyurethane devices. He found similar contracture rates (14%) in all implants regardless of texture or filler material with the exception of polyurethane implants (7%). In the referenced paper, Barone compared textured to smooth silicone to polyurethane expandable prostheses in rabbits. In implantation, only polyurethane made a difference in softening the capsule, but when expansion was applied, textured silicone and polyurethane were both better than smooth silicone in reducing capsular contractures.