Physical and Performance Criteria
Tensile strength may be one of the most critical elements in defining a textile that has a structural role within the body. Defined as the resistance of fabric to breakage when subjected to stress, tensile strength tells us fabric integrity under specified test conditions. At ATEX Technologies, our collaborative approach ensures that we fully engage with our customers to define these test conditions and how an implantable textile component must interact with surrounding tissues and identify any performance requirements needed so we can engineer the product to perform as intended.
Conformability and Elasticity/Dimensional Stability:
At the very beginning of the ATEX product life cycle, our engineers spend a great deal of time collaborating with our customers and asking many questions about the component being created. Our team collects many design inputs that all play a role in determining how the component will be manufactured and how it will perform in vivo. On many occasions, the components that we engineer must be compressed into a delivery catheter and deploy in the body without losing any dimensional stability. Often, the component must also conform to the shape of a vessel or organ without folding, creasing or losing physical integrity. It is in these cases that ATEX particularly excels. Right from the beginning we consider how this can be accomplished reliably and consistently. Our team employs its advanced CAD software systems to tailor the product to the exact dimensions, profiles and performance properties required throughout the component. We can also design a product to have specific characteristics in certain regions or zones. Today’s medical device manufacturers are facing more and more pressure to design smaller, multi-functional devices that can be delivered through tight delivery catheter spaces and small openings in the body. More and more, open procedures are being replaced by minimally invasive ones so the need for conformable solutions that can be compressed and then regain their shape and functionality upon deployment. At ATEX Technologies, Inc., we have worked on hundreds of projects where we have successfully engineered textile solutions that not only perform as intended, but also can be compressed and folded without compromising functionality. By engineering textile layers and patterns, we can ensure that your device not only fits into small spaces, but also perfectly suited for their use within the body.
Porosity and Permeability:
Textiles are made from a series of interlaced yarns. Whether those yarns pass over one another in a perpendicular over-under pattern as with weaving or through a series of interconnected loops evident in knits, the spaces in between the yarns are as important as the yarn itself. Those spaces, technically referred to as pores, impact many characteristics to the textile including the ability to stretch (this is also affected by material choice and surface characteristics) and allow gases and liquids to pass through the structure. This ability to allow or prevent liquids and gases to pass is characterized as permeability. Depending upon the clinical application for which the device component will be used, leveraging the degree of porosity and permeability within a textile can enhance product performance. In general, the higher the porosity, the higher the permeability of the fabric. However, ATEX is also able to treat the component with coatings that may modify these features even further. Porosity and permeability become very important features of implantable medical components especially when a fluid barrier may be desired or when the voids or pore size must be controlled to ensure that cells can proliferate and that healing can be optimized.
Surface characteristics are distinguishing features or properties related to the look, feel and performance of a textile. Surface characteristics may include color and pattern as well as texture/lubricity. Surface characteristics can be inherent in a fabric or they can be enhanced or modified during fabrication. By modifying surface characteristics of fabric we can enhance the textile in unexpected ways. For example, by adding crimps to a woven tube, we can increase elasticity in a textile type not known for high stretch. The addition of coatings and dyes can have a profound impact on product performance by enhancing visibility of the component and modifying permeability to liquids and gases. The surface characteristics of an implantable medical textile are intrinsically related to how the component will work. For example, introducing a crimp pattern to a prosthesis may allow for component elongation and reducing kink. Introducing barbs to a suture may allow for self-tightening and stabilization in delicate cosmetic procedures. The presence of a seam-line may affect how closely a component can lie against an internal surface. And, the addition of coatings may affect implant permeability to gas or liquid and even cells. At ATEX, our engineers are experts at marrying the fit, form and function of your component so that your product is perfectly engineered for the space, and job, the component is meant to do.