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Background: Pirfenidone (PFD), a new antifibrotic and antiinflammatory agent, prevents and resolves fibrous tissue. This study evaluated the effect of PFD on adverse events in mammary implants using an animal model. Mammary implantation, the most frequent aesthetic surgery, may present several complications after surgery such as swelling, capsule contracture, hardness, and pain., Methods: Wistar rats underwent submammary implantation with either smooth or textured silicone gel implants and were administrated 200 mg/kg of PFD daily. The control group received saline. The animals were killed at 8 weeks. The capsular tissue of both implants was removed for histologic and molecular analyses., Results: Typical postaugmentation periimplant capsules with opacity on adjacent tissues developed 8 weeks after silicone implantation. No significant differences were observed between the textured and smooth implants in any analyzed parameter. Clearly, PFD reduced capsule thickness around submmamary tissue, fibroblast-like cell proliferation, and recruitment of inflammatory cells. The total cell numbers per field were reduced as well. In contrast, the control group presented abundant mononuclear cell infiltration and fibroblast-like cell proliferation. The total content of collagen in the PFD group was 50% less than in the control group. Fibroblast cells displayed 45% less activated phenotype in the PFD group than in the control group, as determined by immunohistochemistry techniques. In the PFD animals, transforming growth factor-beta (TGF-beta) decreased 85% and collagen 1 gene expression 60%, compared with the control group., Conclusion: The findings show a positive effect of PFD on mammary contracture in 10 rats. Despite the small number of animals, the differences found in 10 control rats encourage the authors to propose a larger study later and to suggest PFD as a potential preventive strategy in human mammary implantation surgery.

Background: The most common complication experienced by patients who have undergone mammary implant surgery is capsular contracture. This matter concerns physicians and patients, but to date, there is no effective way to avoid this complication. Surgical intervention usually is required. In 2002, the use of zafirlukast, a leukotriene inhibitor (a drug used for asthma treatment), was reported for the treatment of capsular contracture, with good results., Methods: For this study, 30 female Wistar rats were used. These animals received two silicone implants each: one with a smooth surface and one with a textured surface. All the animals received daily intraperitoneal injections for 90 days and were divided as follows: control group (C) receiving only saline solution, experimental group 1 (E-I) receiving 1.25 mg/kg/day of zafirlukast, and experimental group 2 (E-II) receiving 5 mg/kg/day of zafirlukast. Histologic analysis used hematoxilin and eosin to verify vessels, capsule thickness, and inflammatory cells. Immunoistochemical analysis with smooth muscle anti-actin antibody was used for myofibroblast verification. Picro-Sirius under polarized light was used for collagen analysis., Results: Textured implant experimental groups presented smaller numbers of vessels, thinner capsules, lower collagen density, and smaller numbers of mastocytes and eosinophils than the control group. No significant differences were found in smooth surface implants, as compared with the control group., Conclusion: Zafirlukast reduced the occurrence of factors directly and indirectly connected with capsular contracture.

This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity against Stapylococcus epidermidis. Silicone blocks (1 x 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was 63.307 microm in group 1, 111.538 microm in group 2, 43.076 microm in group 3, and 30.384 mum in group 4. The differences between groups 2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation.

One of the most important risk factors in orthopedic surgery is implant-associated infection. Adhesion and colonization mediated implant infections are extremely resistant to antibiotics and host defences and frequently persist until the biomaterial or foreign body is removed, which is standard therapy. Tissue damage caused by surgery and foreign body implantation increases the susceptibility to infections, activates host defences and stimulates the generation of inflammatory mediators including radicals that are further aggravated by bacterial activity and toxins. Nearly one third of implant-related infections can be prevented by strictly following established infection control guidelines. However, a significant number of implant-associated infections remains. The escape of bacteria from host defence and antibiotic therapy makes the development of infection-resistant materials as anti-microbial drug delivery systems feasible. This concept consists of the sustained delivery of antimicrobial drugs into the local microenvironment of implants avoiding systemic side effects exceeding usual systemic concentrations by magnitudes of order.