Time is critical when a patient is undergoing surgery. The longer the patient’s internal tissue is exposed, the greater the risk. The sooner a patient can be closed up and begin recovery, the greater the chances for a healthy recovery.
Maxillofacial surgeons at the Cliniques universitaires Saint-Luc, Université catholique de Louvain (UCL) in Belgium, often need to reconstruct bones in a patient’s skull. Recent examples include patients with a jaw ravaged by cancer or an eye socket crushed in a car accident.
3D printing physical bone models
The surgeons use paper 3D printing technology from Mcor Technologies to recoup hours from traditional surgical procedures. Working from the digitally scanned contours of patients’ bones, doctors push a button to create full-size 3D physical models they can use as surgical guides.
Since the model is a facsimile of the patient’s actual physiology, surgeons can use it to precisely shape metal inserts that fit along a patient’s residual bone. The insert might be a plate that supports a damaged mandible or a titanium mesh for reconstructing a damaged eye socket. Without 3D physical models to work from, surgeons would be forced to rely on time-consuming trial and error to shape the metal implants and risk potential tissue damage.
“With each procedure, we can easily win an hour in the operating room, and that’s a major benefit for the patient,” said Professor Raphael Olszewski, a surgeon and head of the university’s oral and maxillofacial surgery research lab (OMFS Lab, UCL). “We open the patient up, slide in the device, check the fit and start the patient’s recovery.”
The 3D physical skull and mandible models are produced by an Mcor Matrix paper-based 3D printer. To create a 3D model, Olszewski’s team takes a CT or cone-beam CT scan of the patient and uses Maxilim software to export the section of bone they’re interested in. They quickly transform the 3D file into a printable, watertight solid and print the bone model with ease.
Making a change
The team purchased the Mcor 3D printer after five years of using a ZPrinter (resin powder-based 3D printer). One reason for the change in printers was that models from the ZPrinter required an extensive post-processing step that used toxic chemicals (cyanoacrylate). The chemicals required a special license to handle and a special room for the post-processing. Olszewski’s team found the chemicals incompatible with education and healthcare.
“We went looking for an eco-friendly solution and found Mcor,” said Olszewski. Mcor 3D printers create models from paper (standard Letter/A4 sheets). When the sheets are cut and bound together, the model is tough, durable and stable—no infiltration is required. After use, models can be disposed of in the recycling bin for cradle-to-grave sustainability.
Mcor 3D printers use water-based adhesive—no toxic fumes, lasers, airborne powder or toxic resins—enabling the machine to easily coexist in an office or classroom. Part cost is 5% of other technologies’ costs, and total cost of Mcor ownership is a fraction of that of the competition.
Olszewski estimates that a model made with Mcor costs about half that of the ZPrinter and about one-tenth that of stereolithography. With Olszewski’s team making models every day, that’s a savings of more than 20,000 € (≈$21,930) per year.
“The Mcor 3D printer gives us a really affordable 3D model that opens up many possibilities for 3D modeling in maxillofacial surgery,” said Olszewski.
In addition to creating models of surgical patients, Olszewski’s team creates models for the lab. The team is constantly refining its processes so that surgical guide use is increasingly precise. One way the team does this is by CT scanning models and superimposing the images on CT scans of patients. This way, the team can gauge the accuracy of modeling and improve the success of the surgeries. The ease and affordability of producing 3D physical skull models is enabling Olszewski’s team to constantly expand the range of procedures that can be accelerated using 3D printed surgical guides.
Though powerful, the Mcor 3D printer is intuitive, noted Olszewski, even for busy surgeons who need to constantly focus on their craft. The team has also discovered that Mcor models, though paper, can be sterilized. That means surgeons will soon be bringing them into the operating room. As 3D printing’s role quickly evolves, Olszewski sees 3D printing as a powerful, affordable and accessible alternative to highly expensive neuro-navigation systems that ensure accuracy in surgery.
“There are many potential applications in medicine for Mcor’s affordable and eco-friendly process,” said Olszewski. “Look for 3D paper printing not only in surgery, but in medical equipment engineering and biomedical engineering. We’re really at the beginning.”