A Polyethylene is the most popular plastic. Polyethylene is usually a mixture of similar polymers of ethylene with various values of n. Many hip replacement implants and almost all total knee replacement implants do contain ultra-high molecular-weight polyethylene (UHMWPE). This plastic provides cushioning and movement.
Polyethylene is a common plastic and it is often one of the materials used in medical implants because it is an acceptable synthetic polymer that is biologically inactive and does not degrade in the body. However, some polyethylene implants are considered better than others.
A long-term follow-up study carried in Australia confirmed that hip implants which contain crossed-linked polyethylene (XLPE) mainly lower the risk of a patient wanting revision surgery after a total hip replacement when compared to the effects of implants that include the conventional polyethylene (CPE) components. High-density polyethylene (HDPE) solid implants have been used by plastic surgeons since the 80s for facial augmentation purposes.
