Cap component for an endoprosthesis, and endoprosthesis or artificial joint comprising said component

A cap component for an endoprosthesis, the cap component comprising:

• a convex or flat sliding surface;
• the cap component being designed to enclose part or all of an associated bone joint part;
• the cap component and/or a first base material of the cap component having a modulus of elasticity that is about equal to bone material of the associated bone joint part;
• and
• a facing surface of the cap component facing the associated bone joint part being at least partially coated with a first metal or with particles of the first metal.

An endoprosthesis comprising:

• an insert component for a first bone joint part of a first bone, the insert component having a sliding surface, and
• a cap component for a second bone joint part of a second bone, the cap component including:
• a sliding surface;
• the cap component being designed to enclose part or all of the second bone joint part;
• the cap component and/or a first base material of the cap component having a modulus of elasticity that is about equal to bone material of the second bone joint part;
• and
• a facing surface of the cap component facing the second bone joint part being at least partially coated with a first metal or with particles of the first metal,
• wherein the sliding surface of the insert component is in sliding contact with the sliding surface of the cap component.