With the advent of inexpensive and highly accurate 3D printing devices, a tremendous flurry
of research activity has been unleashed into new resorbable, polymeric materials that can be printed using
three approaches: hydrogels for bioprinting and bioplotting, sintered polymer powders, and solid cured
(photocrosslinked) resins. Additionally, there is a race to understand the role of extracellular matrix components
and cell signalling molecules and to fashion ways to incorporate these materials into resorbable
implants. These chimeric materials along with microfluidic devices to study organs or create labs on
chips, are all receiving intense attention despite the limited number of polymer systems that can accommodate
the biofabrication processes necessary to render these constructs. Perhaps most telling is the limited
number of photo-crosslinkable, resorbable polymers and fabrication additives (e.g., photoinitiators,
solvents, dyes, dispersants, emulsifiers, or bioactive molecules such as micro-RNAs, peptides, proteins,
exosomes, micelles, or ceramic crystals) available to create resins that have been validated as biocompatible.
Advances are needed to manipulate 4D properties of 3D printed scaffolds such as pre-implantation
cell culture, mechanical properties, resorption kinetics, drug delivery, scaffold surface functionalization,
cell attachment, cell proliferation, cell maturation, or tissue remodelling; all of which are necessary for
regenerative medicine applications along with expanding the small set of materials in clinical use. This
manuscript presents a review of the foundation of the most common photopolymerizable resins for solidcured
scaffolds and medical devices, namely, polyethylene glycol (PEG), poly(D, L-lactide) (PDLLA),
poly-ε-caprolactone (PCL), and poly(propylene fumarate) (PPF), along with methodological advances
for 3D Printing tissue engineered implants (e.g., via stereolithography [SLA], continuous Digital Light
Processing [cDLP], and Liquid Crystal Display [LCD]).
3D printing processes for photocurable polymeric materials: technologies, materials, and future trends
