How is compression molding technology used in making implantable medical devices?

Compression molding in implantable medical devices

The components produced with this technology are usually present in knee and hip prostheses.

Concerning hip prostheses, the component made with compression molding is the cup which constitutes the part of the implant that is inserted into the pelvis. This is because the molded material, polyethylene, is very durable and resistant to wear and tear from friction.

Concerning knee prostheses, the part made is the meniscus. Also in this case the use of polyethylene is given by its characteristics: inert and hypoallergenic, and with a high density that provides the sliding surface.

But how does the compressoin molding of plastic material take place?

The compression molding process consists in compressing the plastic material (polyethylene powder) inside one or more impressions, obtained in a mold. The special feature of this technology is that the mold is heated.

The heat of the mold fluidizes the thermosetting material which, compressed by the press, gives shape to the piece.

There are, of course, various factors which determine the quality and mechanical resistance of the components made with this technology.

Among these, the greatest impact are related to the applied pressure and the mold heating temperature.


The main characteristics of these components are the absence of burrs and joint lines.


Parts produced by compression molding have a very high structural stability.


This technology is often the most efficient manufacturing method for producing simple, mostly flat, large parts.