Capsular contracture around silicone miniimplants following bacterial contamination: an in vivo comparative experimental study between textured and polyurethane implants.

[BACKGROUND] Capsular contracture remains a problem following breast implant surgery. Although impact of biofilm and implant surface on capsule formation has been demonstrated, interaction of microorganisms with different surface types has not been clarified yet. We aimed to compare the ability of biofilm formation of implants with different surfaces, under standard conditions and to demonstrate its impact on capsular contracture.

[METHODS] Twenty-four rats were divided into four groups. Mini-implants with three different surfaces (fine-textured, rough-textured and polyurethane) were placed on the dorsum of each rat. In Group-1, sterile implants were placed in submuscular pockets. In Group-2, implants were incubated in Staphylococcus epidermidis medium before implantation. In Group-3, before implantation, implants were immersed in Rifamycin solution following bacterial contamination. In Group-4, sterile implants were immersed in Rifamycin solution before implantation, and served as the control group. Rats were sacrificed at three months. Clinical, microbiological, histological and immunohistochemical evaluations were performed.

[RESULTS] Capsule contracture developed only on infected rough-textured implants. Rough-textured and polyurethane implants showed more biofilm formation than fine-textured implants. Capsule thickness and inflammatory cell density were higher on rough-textured implants compared to fine-textured implants (p = 0.004). Actin sequence was parallel and concentric on fine-textured and rough-textured implants; but was in irregular array on polyurethane implants.

[CONCLUSION] In presence of bacterial contamination, rough-textured implants have the most propensity of developing capsular contracture comparing to fine-textured and polyurethane implants at three months after implantation. Despite high bacterial load and biofilm formation, polyurethane implants are resistant to capsule contracture due to surface characteristics.