As the world grapples with an unprecedented crisis, 3-D printing has emerged as a viable temporary manufacturing option to supplement supply lines that are at capacity.
For weeks now, we’ve heard how 3-D printing has accelerated the delivery of necessary personal protective equipment (PPE) to healthcare workers on the frontlines. But what materials are they using? What printers are they employing? Can dental professionals do anything to help.
One of the first reported examples of 3-D printed PPE was a face shield. On March 18, Prusa Printers of the Czech Republic announced it had spent the previous three days working on a face shield to protect frontline workers.
Why face shields and not masks and respirators? As far as I know, none of the crowdsourced designs for masks have been officially validated and approved for use. Therefore, it’s unclear if printed masks are sealing properly and protecting users from airborne viruses or if particulates are passing through.
In addition to fit and functionality, there also are questions about how long the virus lives on materials, if they are too porous, and if the warm, humid environment surrounding the mouth creates a breeding ground for germs.
Currently, we don’t know the answer to these questions. Furthermore, the possibly of inadequate design or materials poses too great a risk for those dealing with the virus firsthand.
Face shields, however, do not have the same strict requirements. Due to their simplistic form, 3-D printed shields can be expected to function properly. They protect wearers from infected individuals who may directly cough or sneeze on them. They not only suit frontline healthcare workers, but also police officers, grocery store workers, and other essential personnel who still come into contact with other people regularly.
Prusa’s face shield headband design has been verified by the Czech Ministry of Health and has received feedback from physicians at the University Hospital Vinohrady in Prague.
Currently, most face shields are being printed on fused deposition modeling (FDM) printers. This printing technology extrudes a filament (a long strand of spooled thermoplastic) through a printhead to deposit material one layer at a time. It’s not common in dentistry except for custom impression trays.
How You Can Pitch In
If you have access to an FDM printer, reach out to the manufacturer to see what materials it recommends for face shield headbands. From what I’ve seen, headbands are being printed in PETG, which allows the printed object to have some elasticity while still maintaining rigidity. It also does not shatter as easily as PLA does. If PETG is not available, ask your manufacturer what other materials could be substituted.
Once you’ve determined which materials to use, talk to healthcare professionals to see if they need the PPE you’re interested in making. If there is a need for that particular PPE, be sure to ask about proper sterilization practices and how best to package and ship. Many healthcare systems won’t accept packages unless they follow certain shipping protocols.
Once you’ve had a conversation with the manufacturer about materials and with healthcare professionals about receiving your PPE, it’s time to start helping!
However, most dental facilities don’t have an FDM printer. So can you still help? That depends on your printer. Most dental printers have a small printing area. But if you have a large enough print bed to accommodate the face shield headband (200 by 150 by 85 mm), ask your printer manufacturer if there is a material it recommends.
What Else You Can Do
Face shields are a great way to help with the shortage of PPE, but dental 3-D printers also may be able to help with some of the other major problems we’re facing during this crisis. For example, some researchers have been looking to 3-D printing to produce ventilation splitters, which would allow a ventilator to be used by two patients.
EnvisionTEC, one of the most successful dental 3-D printer companies, is working with the Food and Drug Administration (FDA) and Detroit area hospitals to design and test a functional ventilation splitter. These splitters could effectively double the current ventilator capacity and give Ford, GM, and other companies a chance to ramp up ventilator production.
While 3-D printers are being used to help with PPE shortages and ventilator shortages, they also can help solve the testing shortage by producing nasopharyngeal swabs to collect specimens for testing.
A consortium of 3-D printing experts from companies like EnvisionTec, Formlabs, and Carbon and academia has been working closely with the Clinical Microbiology Division at Beth Israel Deaconess Medical Center to design and test 3-D printed nasopharyngeal swabs. Designs created by the consortium have gone through the FDA’s in-depth certification process.
The 10 stages of mechanical testing that the FDA requires includes a two-part absorption test, a biological/chemical testing procedure to ensure the swab absorbs viral RNA particles and does not interfere with PCA/reagents, and a sample collection testing procedure. Testing also determines if the material is chemically safe, if it can bend 180 degrees without breaking, and whether the swab can collect enough virus particles from the nasal passage to effectively test.
EnvisionTEC and other companies associated with the consortium have materials and designs that have passed these tests and are now able to produce up to 4 million swabs a week. The swabs can be sourced directly from the consortium or through state emergency management agencies.
There’s been a lot of exciting news about how 3-D printing can help during this crisis, and those of us in the dental community desperately want to help where we can. But before you start printing, make sure you’ve done your research.
Talk to your 3-D printer manufacturer and healthcare professionals about what they need and how to properly deliver it to them. We can produce parts to help with this crisis. Whether it’s masks, face shields, ventilator splitters, or nasopharyngeal swabs, we’re responsible for making sure that what we print is functional and safe.
Mr. Montealegre is director of technical operations at Apex Dental Milling in Ann Arbor, Michigan. He works collaboratively with DENTAL ADVISOR on training and educating the dental industry in digital workflow, CAD/CAM, 3-D printing, and materials. He can be reached at (866) 755-4236 or via email at firstname.lastname@example.org.