3D printing often results in more porous surfaces than other production methods, making it easier for microbes to stick to the product. Sterile 3D printing exists, but it takes highly specialized procedures. Because of this, it is often only found in hospitals and research laboratories.
When not produced with already sterile material and under sterile conditions, the printed items need sterilization. Medical sterilization uses heat, radiation, and chemical processes. Devices made for use with patients must be able to withstand repeated exposure to these processes. Most common 3D printing materials will warp, melt, or lose tensile strength during sterilization.