Surface Areas of Textured Breast Implants: Implications for the Biofilm Theory of Capsule Formation

Background: Increased surface area of mammary implants is suggested as a causative agent for the development of biofilms, which may lead to capsular contraction. The aim of this study was to quantify the surface areas of round implants of different textures and examine how these data can be interpreted with regard to clinical observation. Methods: Surface areas of textured round breast implants were calculated from previously reported confocal scanning microscopic assessment, and dimensions sourced from 3 breast implant manufacturers (McGhan, Mentor, and Silimed). Statistical comparisons were made between manufacturers for different implant volumes, profiles, and texturing. Results: There was a difference in surface area between manufacturers for all implant profiles and between manufacturers for equivalent volume implants (F (3, 253) = 2,828.87; P < 0.001). Silimed polyurethane implants (mean area = 6.12 x 10(6) mm(2)) was the highest. Natrelle (mean area = 1.2 x 10(6) mm(2)) was the next highest, followed by Siltex (mean area = 4.8 x 10(5) mm(2)). Mentor smooth implants (mean area = 4 x 10(4) mm(2)) had the lowest mean surface area. There were no differences in surface area between the different profiles for Siltex, Silimed polyurethane, and Mentor smooth implants of the same volume. Conclusions: The increased surface area produced by texturing, although different between manufacturers, seems to provide protection against capsular contraction. Correlation with clinical data indicates that the surface area alone cannot account for these differences. Smooth implants, which have the smallest surface area have the highest incidence of capsular contraction. These data are at odds with the biofilm theory of capsular contraction.