- Metal Ball and Polyethylene Liners
- Ceramic Ball and Polyethylene Liner
- Metal Ball and Metal Liner
- Ceramic Ball and Ceramic Liner
Ceramic Ball and Polyethylene (Plastic) LinerCeramic heads are harder than metal and are the most scratch resistant implant material. The hard, scratch resistant, ultra-smooth surface can greatly reduce the wear rate on the polyethylene bearing. The potential wear rate for this type of implant is less than Metal-on-Polyethylene.
Ceramic-on-Polyethylene is more expensive than Metal-on-Polyethylene, but less than Ceramic-on-Ceramic. In the past, there had been incidents of fractures, but newer, stronger ceramics have resulted in considerable reduction of fracture rates (0.01%) compared to the original brittle ceramics.
Some ceramic-on-polyethylene implants utilize a vitamin E-stabilized, highly crosslinked polyethylene bearing material. Vitamin E, a natural antioxidant, is expected to improve the longevity of the implant bearings used in total joint replacements. In laboratory testing, these liners have demonstrated 95-99% less wear than some other highly crosslinked polyethylene liners.
Ceramic-on-Polyethylene implants have a potential wear at a rate of about 0.05 millimeters each year, i.e. 50% less than Metal-on-Polyethylene. The newer, highly crosslinked polyethylene liners have shown potential wear rates as little as 0.01 millimeters each year.