| Product Specification

MediTECH® Implantable Polymers

Polymer materials for the production of long-term medical implant applications.

Specifications

Product TypeImplantable Polymers
Production MaterialsUHMW-PE (Chirulen® and Extrulen®) PEEK (Zeniva®)
Size Ranges6mm to 80mm (ZA-500 Rods) 15x150x400 mm and 40x500x1000mm (ZA-500 Plates)
ApplicationsOrthopedic and Dental Implants, Spinal cages, cervical interbody fusions, etc.

Overview

MediTECH® implantable polymers are a portfolio of high-quality and versatile thermoplastic shapes used to manufacture long-term orthopaedic and dental implants. The implantable polyetheretherketone (PEEK) and ultra-high molecular weight polyethylene (UHMW-PE) products offer complete traceability from resin to stock shape and are pre-assessed for compliance. Cross-linking and antioxidants can further enhance these products, offering customizability to meet the application requirements. Antioxidants such as vitamin E can also be blended into the resin prior to conversion in order to prevent oxidation and material degradation of the semi-finished stock shape.

Versatile Polymers and Thermoplastics for Dedicated Medical Implant Applications

MediTECH implantable polymers come in two major types:

  • Implantable UHMW-PE

  • Implantable PEEK

Implantable UHMW-PE products are best suited for dynamic joints, such as shoulders, knees, hips, elbows, wrists, and spines. There, they may find application as joint liners or as total joint replacements. These products are made from Chirulen® and Extrulen®, which are exceptionally robust medical-grade polyethylene materials designed with high-level consistency and cleanliness.

Chirulen® is a UHMW-PE that exhibits exceptional properties due to its specialized processing via compression molding. Its unique molecular structure, characterized by exceptionally long polymer chains, gives Chirulen® remarkable strength, wear resistance, and biocompatibility. These attributes make it a prime candidate for demanding medical applications such as dynamic joint liner for hip, knee, and shoulder replacements. Extrulen® is the other UHMW-PE whose production has a distinct approach to it shaping. It exhibits similar properties to those of Chirulen® but is produced in an extrusion process involving a feed screw and heating chamber. It’s more suited for high-volume production featuring high dimensional precision, especially for delicate anatomical shapes.

Zeniva® (PEEK) is a high-performance polymer featuring exceptional biocompatibility and radiolucency. It’s a highly preferred material for orthopedic and spinal applications. Zeniva® PEEK's remarkable strength, similar to a bone, allows it to seamlessly integrate with the human body, bearing weight and facilitating movement. MediTECH Zeniva polymers are designed to exhibit the moldability characteristics needed for complex implants such as dental crowns, bridges, abutments, and orthopedic implants such as spinal fusion cages, suture anchors, and craniomaxillofacial reconstruction.

Direct Compression Molding Technology Produces Highly Accurate Polymer Shapes

MediTECH implantable polymers are designed using direct compression molding technology. This technology ensures the shapes closely match the finished products. The technique is more efficient as it reduces the time, resources, and scrap involved in machining. This also simplifies the compliance process for customers as they only have to certify their added machining work since the near net shape is already pre-assessed.

Since UHMW-PE is a unique polyethylene with a precise molecular weight, it is used as a raw material as a fine powder instead of pellets. Chirulen® and Extrulen® are produced using different techniques. For instance, Chirulen® shapes are obtained with compression molding, and Extrulen® shapes are obtained by ram extrusion.

Chirulen® is produced by feeding the powder in a heated mold cavity. It undergoes immense pressure that compacts the particles together, fusing them into a solid form. The process transforms the powder into stock shapes or custom near net shapes, ready to be machined into the desired parts.

Extrulen® is produced by feeding the powder into a heated chamber with a rotating screw. This screw mixes and pushes the material forward until it reaches a die at the end, shaping the molten UHMW-PE into a continuous profile, which then cools and solidifies.

Chirulen® is best suited for designing intricate shapes with undercuts, while Extrulen® is optimal for high-volume production of simpler profiles. 

Zeniva® is produced by heating and precisely shaping PEEK granules within custom molds, achieving intricate geometries and anatomically accurate forms. Often reinforced with carbon fiber for enhanced strength, these molded implants become the building blocks for various medical devices, ready to bear the weight of movement and improve lives.

References

Mitsubishi Chemical Advanced Materials [Internet]

Mitsubishi Chemical Advanced Materials [Internet]

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