Low Wear Rate and Longer Lifetime

Lower Osteolytic Potential

Studies show that ceramic wear couples have an osteolytic potential that is roughly 50 times lower than highly cross-linked polyethylene. This is a result of both the low biological activity of ceramic wear particles and the low wear volume. The wear rate is independent of the ball head diameter, i.e. large ceramic ball heads have no effect on the wear behavior. In contrast, polyethylene wear couples have a major disadvantage due to increased polyethylene wear.

Longer Implant Lifetime with Ceramic Ball heads

Ceramic ball heads reduce polyethylene wear to significantly less than 0.1 mm per year. Unlike metal ball heads, ceramic ball heads cannot be scratched. Compared to metal/polyethylene solutions, BIOLOX®forte/polyethylene wear couples reduce the rate of implant loosening and revision surgery and the associated complications by 2-5 times.

Clinical results show that the wear rate with polyethylene is more than 0.2 mm per year, regardless of the prosthesis system, when metal ball heads are used. Scratches on the surface of a metal ball head lead to even greater polyethylene wear. The surface of metal ball heads often has small scratches. Laboratory studies using scratched metal ball heads indicated an increase in the amount of polyethylene wear debris of roughly 30 times.

In vivo linear Wear Rates

In vivo linear Wear Rates

Linear wear rates of different wear couples: Different XPE versions show greatly varying results in metal/XPE studies.

Sources
Greenwald AS, Garino JP. Alternative bearing surfaces: the good, the bad, and the ugly. J Bone Joint Surg 83-A, Suppl 2 Pt 2: 68-72, 2001;
Hendrich C,Wollmerstedt N, Ince A, Mahlmeister F, Göbel S, Nöth U. Highly Crosslinked Ultra Molecular Weight Polyethylene- (UHMWPE-) Acetabular Liners in combination with 28 mm BIOLOX® heads, in: Benazzo F, Falez F, Dietrich M (eds). Bioceramics and Alternative Bearings in Joint Arthroplasty, 11th BIOLOX® Symposium Proceedings. Steinkopff Verlag Darmstadt: p.182, 2006;
Martell JM, Verner JJ, Invaco SJ. Clinical performance of a highly cross linked polyethylene at two years in total hip arthroplasty: A randomized prospective trial. J Arthroplasty 18 (7 suppl. 1):55-59, 2003;
Zichner LP, Willert HG. Comparison of Alumina Polyethylene and Metal Polyethylene in Clinical Trials. Clin Orthop Rel Res 282:86-94, 1992;
Zichner LP, Lindenfeld T. In-vivo-Verschleiß der Gleitpaarungen Keramik-Polyetyhlen gegen Metall-Polyethylen. Orthopäde 26:129-134, 1997;
Bragdon CR, Barrett S, Martell J, Greene ME, Malchau H, Harris WH. Steady-State Penetration Rates of Electron Beam–Irradiated, Highly Cross-Linked Polyethylene at an Average 45-Month Follow-Up. J Arthroplasty 21/7: 935-943, 2006; Manning, DW, Chiang PP, Martell J, Galante JO, Harris WH. In Vivo Comparative Wear Study of Traditional and Highly Cross-linked Polyethylene in Total Hip Arthroplasty. J Arthroplasty 20/7: 880-886, 2005

Recommended Contacts

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