Polyethylene (abbreviated PE) or polyethene (IUPAC name polyethene or poly(methylene)) is the most common plastic. The annual global production is around 80 million tonnes.

Its primary use is in packaging (plastic bags, plastic films, geomembranes, containers including bottles, etc.). Many kinds of polyethylene are known, with most having the chemical formula (C2H4)n. Thus, PE is usually a mixture of similar organic compounds that differ in terms of the value of n.

Polyethylene is in all respects suitable for primary and secondary cranioplasty. Combined with 3D CAD- CAM method excellent aesthetic and functional result was achieved. In a study no case of infection occured. Proper preoperative preparation is important ¹⁾.