Inside the 3D Printing Process of Life-Saving Bioresorbable Splint
Surgeons at the University of Michigan's C.S. Mott Children's Hospital recently implanted a 3D-printed tracheal splint to open up the airways and save the life of eighteen-month old Garrett Peterson, who was suffering from a condition called tetralogy of Fallot with absent pulmonary valve. Garrett is the second baby whose life was saved with the bioresorbable device, developed at the University of Michigan by doctors Glenn Green and Scott Hollister. The device was created directly from a CT scan of Garrett's trachea and bronchi, integrating an image-based computer model with laser-based 3D printing to produce the splint. In this video, research specialist Colleen Flanagan explains the process behind 3D printing the splint.
Transcript
00:00:06 >> Right now I'm standing in front of a 3D printer. This particular printer has a selective laser-sintering machine, which is a rapid prototyping machine that we use to build custom implants for clinical use and also for research use in our lab. What's going on inside the machine is a layer of polycaprolactone, which is a biodegradable polymer is getting deposited on a building platform. And a laser is then passing over that in a 2D pattern to melt the powder, and it's building up the tracheal splint layer by layer in the Z direction. You can see the faint shadows of the 2D cross sections of the tracheal splint on the build platform.
00:00:53 And in a few moments you'll see those areas start to darken as the laser traces out its 2D path outlining the cross section of the next layer on the build platform. One of the splint designs is 23 millimeters in length. In order to populate the platform with about 30 copies of that splint it takes roughly three and a half hours to build. And it's 288 layers. So our 3D printing of the tracheal splint build is done. And I am going to open up the machine. Opening the door. And now I am carrying the build platform out of the machine.
00:01:36 Now I'm putting the build platform into our sieve, which will help us separate the parts from the un-sintered powder. This is a hydraulic platform that's raising the platform up. You can see the non-sintered powder on top, which we will push off. So now I am just using some forceps to take some of these splint designs out of the powder bed. And you can see that the non-sintered powder is loose. And it comes off relatively easily. So we will remove all of these splints, separate them from the powder, and then the next step will be to use an air blasting cabinet to get the remainder of the powder off of these implants.
00:02:26 OK. So now what I'm doing is I'm just using an air blasting gun and removing the powder. And the longer splint is designed to go over the region on the left bronchus that is collapsing when the patient exhales. And the smaller splint is designed to go on to the area on the right bronchus that's collapsing. [ Silence ]