Contraction of fibrous capsules which form around breast prostheses remains the most common complication of breast reconstruction procedures. The goal of this Phase II project is to develop a combination of surface modifications for breast prostheses that will improve tissue bonding to the silicone (SR) surfaces, while decreasing inflammation, fibrous capsule thickness, and capsular contraction. The study will combine three approaches which have been shown to modulate these tissue responses: l) surface porosity of the prostheses, 2) proteins covalently coupled to the prostheses, and 3) fibrosis-inhibiting carbohydrates applied on top of the protein coatings. The surface characteristics of the coated prosthesis materials will be analyzed for uniformity of coating, and the mechanical properties will he tested before and after surface modification. Cell culture assays will evaluate the in vitro bioactivity of each coating and the effects of sterilization, drying and storage on the coatings. Finally, the modified prostheses will be implanted subcutaneously in pigs for 16 weeks. Clinical evaluation for tissue hardness will be assessed by indentation tonometry. Tissue surrounding the implants will be evaluated histologically for bonding to the SR, the presence of inflammatory cells, and the thickness and architecture of collagen in the capsules.
Two million Americans have breast prostheses, with contraction of fibrous capsules being the most common complication. The proposed surface modifications should improve the performance of breast prostheses by greatly decreasing capsule formation and contracture.
