High-tech for Arthroplasty

BIOLOX® components provide wear surfaces with almost perfect sphericity and superior surface finish.

Quality control at all levels –
3D measurement of ball heads

Highest Surface Quality

Precisely executed final polishing gives the ceramic components the lowest surface roughness of all implant materials. The mean roughness of BIOLOX®’s highly polished surface is only around 2 nanometers (0.002 μm).

Exact Sphericity

A maximum variance from a perfect sphere of only 5μm ensures that the components have a superior fit (testing accuracy < 1μm).

The wear-reducing lubrication states A and B can be reached more often with ceramic components.

Synovial fluid Lubrication

We know today that there is no permanent hydrodynamic state of lubrication in artificial hip joints. The continuous shifting between motion and rest and the frequent generation of one-sided stress usually prevent the formation of a permanent lubricating film of synovial fluid. This makes the wear resistance of the articulating materials even more crucial. Three states of lubrication are observed in total hip arthroplasty: fluid film lubrication (A), mixed lubrication (B) and boundary lubrication (C). The especially smooth and hydrophilic surfaces of ceramic components help to ensure that the wear-reducing lubrication states A and B are achieved more often than with other wear couples.

Strong hydrogen bonds provide excellent wettability of the ceramic.

Good Wettability

The strong hydrogen bonds between the ceramic surfaces and synovial fluid give ceramic materials excellent wetting properties that are far superior to those of metal and polyethylene and ensure that an effective lubricant film forms.

High dimensional Stability

BIOLOX® ball heads and cup inserts do not deform under the loads encountered in vivo. This fact, coupled with the enhanced surface finish, is a prerequisite for the high wear resistance of BIOLOX® components. Their excellent dimensional stability comes from their extremely high Young’s modulus and high compressive strength. In investigations made on explanted devices articulated against polyethylene it was demonstrated that BIOLOX® ball heads maintained their dimensional stability even after more than ten years in vivo. It was also determined that the BIOLOX® ball heads still conformed as precisely to the specifications and tolerances as they did at the time they were made.

Recommended Contacts
