4D printing of polymeric materials for tissue and organ regeneration

TLDR

Four‑dimensional printing is an emerging technology that creates stimuli‑responsive 3D structures, offering promising applications in tissue and organ engineering, and has evolved rapidly since its 2013 introduction. This review establishes 4D printing criteria, surveys state‑of‑the‑art advances, and examines its applications in tissue and organ regeneration. The review surveys transformation‑preprogrammed 4D printing and shape‑memory polymer techniques, detailing key technological advances.

Abstract

Four dimensional (4D) printing is an emerging technology with great capacity for fabricating complex, stimuli-responsive 3D structures, providing great potential for tissue and organ engineering applications. Although the 4D concept was first highlighted in 2013, extensive research has rapidly developed, along with more-in-depth understanding and assertions regarding the definition of 4D. In this review, we begin by establishing the criteria of 4D printing, followed by an extensive summary of state-of-the-art technological advances in the field. Both transformation-preprogrammed 4D printing and 4D printing of shape memory polymers are intensively surveyed. Afterwards we will explore and discuss the applications of 4D printing in tissue and organ regeneration, such as developing synthetic tissues and implantable scaffolds, as well as future perspectives and conclusions.