And I'm moderately baffled by a reported need for 3d printing to treat stomach ulcers "less invasively" - standard of care is an endoscopy to diagnose the ulcer (sometimes ulcers can be diagnosed by various imaging modalities, but this is much less sensitive), and if the ulcer needs treatment (visible blood vessel, visible bleeding, or a large adherent clot) you can do it then and there - typically an epinephine injection to slow active bleeding, and then either a clip which will close the ulcer and fall off and pass on its own in a few weeks, or you can apply a heat probe for coagulative coaptation of the blood vessel causing the bleeding. In either case, for the vast majority of ulcers, these treatments will stop the bleeding at the end of the procedure, typically 5-15 minutes. The stomach mucosa will then heal on its own, with the help of proton-pump inhibitors like prilosec.
Not sure how this process is less invasive as it also requires endoscopic placement, or more effective as it would take much longer. I guess it could be helpful in non healing ulcers due to poor blood flow from severe vascular disease or heart failure, although I doubt the printed cells will do too well without a good blood supply.