Abstrato

The effect of fiber spacing and fiber diameter on soft tissue ingrowth for polyethylene terephthalate.

Dale S. Feldman

Variables such as pore size; percent porosity, fiber diameter, and surface roughness of an implanted device determine the speed and completion of ingrowth for a particular application. Clinically, porous implant devices have failed due to inadequate tissue ingrowth; in many cases due to the inability to limit the chronic inflammatory response. For fabric implants, the type of ingrowth and related success is mostly dependent on the fiber diameter and fiber spacing of the fabric. Similarly, the quality and amount of tissue ingrowth is related to this fiber configuration and the resultant inflammatory response. For fabric mesh implants, this can lead to inadequate mechanical support and even erosion of surrounding tissue. Histological images are a good way to determine the fiber spacing and fiber diameter as well as the resultant tissue response. Porous polyethylene terephthalate fabrics composed of varying combinations of fiber spacing and fiber diameter were implanted in the subcutaneous tissue of rabbits to investigate the effect of configuration on tissue response. It was determined that increasing fiber diameter resulted in a decrease in the chronic inflammatory response with a transition occurring between 67 and 72 μm. Although the manufacturer claimed the fiber spacing was closer to the spacing where slight reductions should have decreased the amount and quality of the tissue ingrowth, the measured fiber spacings were too large to be near the threshold levels. The trends seen in this study, however, could be used to assist in design of fabric implant systems to improve clinical performance.