The effect of supporting hydrophilic silicone implants with antibacterial agents by plasma activation on periprostatic capsule formation in the rat models

Several theories have been proposed for the formation of capsular contracture. Additionally, the role of subclinical infection has been supported by both clinical and preclinical studies, and there is broad acceptance that it is a pathogenic pathway. Antibacterial irrigations are used to reduce contamination during breast implant placement. The hydrophobic nature of the breast implant surface is a limiting factor for antibacterial irrigations. This hydrophobic property can cause the solution to run off, leading to a reduction or complete loss of the irrigation's effect. Plasma activation of the implant surface changes its properties from hydrophobic to hydrophilic, thereby allowing the temporary adherence of antibacterial irrigations to the implant surface. In our study, using a rat model, three main groups (A, B, C) with 10 subgroups (6 rats each) were created based on bacterial strain and contamination. Implants were placed in pockets under the panniculus carnosus. Group A1 served as the control, treated with saline only. Plasma-activated implants were treated with saline or antibacterial solution, then contaminated with Staphylococcus aureus and Pseudomonas aeruginosa before placement. After 3 months, implants and capsules were analyzed macroscopically and microscopically. Plasma activation with antibacterial solutions significantly reduced bacterial adhesion, biofilm formation, average capsule thickness, inflammation, fibrosis, mast cell count, and neovascularization. The lowest values were in the A2 (plasma-activated, no contamination) and C3 (plasma-activated, gentamicin, P. aeruginosa) groups, while the highest values were in the B1 (S. aureus, no plasma activation) group. Plasma activation combined with antibacterial solutions made the implant surface hydrophilic, thereby hindering bacterial adhesion and biofilm formation, and significantly reducing average capsule thickness, average inflammation score, fibrosis, average mast cell count, and neovascularization.