Printing an exact copy of the patient

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How medicine uses 3D printing.

On the table is the horizontal section of a skull. White. Matt. With all its external curves and lines, all the complex structures of its inner volumes.

Despite appearances, this is not a real skull. Just a reproduction – accurate to within a few mi- crons – of the skull of a young patient at CHUV (Lausanne University Hospital, Switzerland). It was created on a ProJet 3510 SD, a mid-range, highly accurate printer model designed by 3D Systems, one of the leaders in 3D printing solu- tions.

Printing such an item begins with a traditional scan or MRI. The files are transmitted to the CHUV printing centre where engineers – such as 3D printing specialist Sébastien Martinerie – prepare the digital file. This requires knowledge in both medicine and 3D modelling.

In the printer are two polymer materials owned by 3D Systems: the material which will “hold” the finest elements and the building material itself. Once it's printing, the machine super- poses – one by one – layers 32 microns deep. Every two or three layers, a UV flash hardens the material.

It takes about 15 hours to print a 7cm-high sec- tion of skull. To remove the resin mould, the printout goes in the oven at 65 degrees and then in a bath and receives ultrasonic vibrations. The final touches are made by hand.

Until 2012, the CHUV bought these 3D printouts from external suppliers. Printing them in-house is less expensive and delivery times are much shorter. What is more, they are developing in- house expertise which will enable the teaching hospital to better integrate future evolutions to this promising technology.

The CHUV prints between 30 and 40 pieces a year, most for the hospital’s maxillofacial surgery department, managed by Dr Martin Broome. The section of skull placed on the table helped the surgeon to prepare for surgery and – with ideal precision – to model the implant he will fit into his patient’s damaged orbital floor.


Materials: cells, biomaterials (anionic polymer, synthetic hydrogels, etc.). Printing for pharma- ceutical research or regenerative medicine in tissue engineering (skin, bones, heart, blood vessels and other), close to actual tissue. Teams have also printed cancerous tumours, helping to better study their behaviour.


Materials: biopolymers, iron/manganese, etc. Printing of bioresorbable structures which, once implanted, will support tissue reconstitu- tion (bone tissue, for example) generated by the body itself. Once the tissue has reformed, the scaffold dissolves.

Surgical guides

Materials: biocompatible polymers. Custom printing of cutting guides. True to the sur- geon’s planning, accuracy is greatly improved for bone resection and implants.

Medical Imaging

Materials: polymers. Printing of portions needed (bones, organs, foetus, tumours, etc.). These models help to prepare for surgery (for example, demarcating the zone to be re- moved) and/or implants. Also makes it easier to communicate between specialists, with pa- tients and with students.

External prosthetics

Materials: polymers. Custom printing of supports, corsets, prosthetics or exoskeletal pieces, much faster and less costly than usual production. Perfectly adapted, these elements are also more comfortable for the patient.


Materials: biocompatible (titanium). Easier and less costly printing of perfectly customised implants. They are easier to implant and are structured in a way that promotes integration with the bone, speeding up the healing process and mobility.


Materials: cells, biomaterials (anionic polymer, synthetic hydrogels, etc.). Printing of living and functional organs. Eventually, they could mean organ donation is no longer needed. In the near future, the design of simplified or min- iature organs could reduce or eliminate animal testing.