The difference of material wettability as critical factor in the choice of a tribological prosthetic coupling without debris release

Today, in spite of the long experience acquired in the field of total hip replacements, prosthetic systems are still far from reproducing the natural system. One of the main causes of long term failure is the amount of wear debris produced by the tribological coupling between acetabolar cup and femoral head. The authors carried out experimental research in order to investigate the tribological coupling of various prosthetic biomaterials. Experimental tests were carried out with the pin-on-disc tribometer in dry, water and human serum as lubricant. This study sets new bases for the design of modern hip prostheses: 1. the wettability difference among the materials in tribological coupling, which is the necessary condition to promote efficient lubrication; 2. the use of Peek reinforced with long and unidirectional carbon fibres in the prosthetic field.