StelKast is the first U.S. orthopedic company to provide a highly cross-linked vitamin E blended antioxidant polyethylene, offering superior oxidation resistance in hip and knee implants.

EXp Polyethylene Technology represents an optimal blend of UHMWPE, the antioxidant vitamin E(α-tocopherol), and cross-linking for long-term oxidative stability, preservation of mechanical properties and performance.

• Unlike other highly cross-linked polyethylenes, EXp requires no thermal processing or infusion of antioxidants to stabilize the material.
• EXp liners experienced no failures as a result of dynamic impingement testing.
• The vitamin E blended into the EXp does not elude from the material during extraction studies.
• The morphology of EXp UHMWPE is consistent with conventional UHMWPE—demonstrating no consolidation defects or voids.

Stability

Oxidatively Stable¹
EXp UHMWPE is more resistant to oxidation than conventional cross-linked polyethylene

Long-Term Stability²
EXp UHMWPE remains resistant to oxidation after 5 million cycles of wear testing and artificial aging

Performance

Preserved Mechanical Performance³
EXp UHMWPE retained its mechanical performance after oxidative aging

Reduced Wear⁴
EXp liners demonstrated a 30% reduction in wear against a 36mm BIOLOX®delta head compared to a 36mm cobalt-chrome head

References 1 through 7: Data on file at StelKast. Bench testing is not necessarily indicative of clinical performance.

Download the EXp brochure